Methods and prostheses for connecting porous surface structures and substrates using thermoplastic materials.

Abstract

This invention discloses a method and prosthesis for connecting a porous surface structure and a substrate using a thermoplastic material. A layer of thermoplastic polymer material is placed in the gap between the porous surface structure and the substrate, allowing the porous surface structure to be tightly bonded to the porous structure on which the substrate is located or to a pre-connected porous structure on the substrate. This improves stress shielding and solves the problem of postoperative osteolysis. The prosthesis of this invention has excellent bone ingrowth performance, ensuring that the strength of the substrate is not substantially affected, guaranteeing the basic strength of the connection structure, and optimizing the overall composite structure stiffness, effectively reducing the risk of stress shielding.

Description

[0001] This case is a divisional application.

[0002] Original invention title: Connection structure between porous surface structure and substrate, preparation method and prosthesis

[0003] Original application number: 202010119232.4

[0004] Original application date: February 26, 2020 Technical Field

[0005] This invention relates to connection technology for mechanical structures, and particularly to medical devices, providing a method and prosthesis for connecting porous surface structures and substrates using thermoplastic materials. Background Technology

[0006] Engineering applications often have different requirements for the overall performance and surface properties of mechanical structures. For example, the acetabular cup and femoral stem of an artificial hip joint must meet the fatigue resistance requirements of the prosthesis under dynamic loads during one to two million walking cycles per year for decades after implantation, and the prosthesis surface also has specific performance requirements to ensure a firm bond between the prosthesis surface and the patient's bone structure, preventing the prosthesis from loosening; otherwise, the patient will experience pain, necessitating the removal of the prosthesis and a revision surgery to implant a new one. Other orthopedic implants (such as the spine) have similar requirements. In fact, in other fields, there are also situations where the base and surface have different performance requirements, and a reliable and effective connection between the two is needed.

[0007] Commonly used artificial materials for joint prostheses include titanium alloys, cobalt-chromium steel alloys, and stainless steel, which cannot form an effective biological or chemical bond with bone. The interface between the prosthesis and bone is generally achieved primarily through physical / mechanical bonding. For example, highly polished prosthesis surfaces and bone tissue cannot form an effective bond, so it is necessary to enhance osteoconduction, osteoinduction, and bone regeneration to accelerate or strengthen the bond between bone tissue and the prosthesis surface, further improving bone ingrowth or bone integration performance. Sometimes, titanium wires or titanium beads can be used to form a porous coating on the surface of the prosthesis (such as an acetabular cup / femoral stem) using methods such as sintering or diffusion welding. Alternatively, using metal 3D printing additive manufacturing processes, vapor deposition processes, etc., a thin sheet 0001 with a porous structure can be prefabricated, and then the thin sheet 0001 can be bonded to the solid base 0002 of the prosthesis using diffusion welding, such as... Figure 1As shown, these methods provide a porous surface for the prosthesis, allowing bone tissue in contact with the prosthesis to regenerate. New bone tissue fills the interconnected porous structure, achieving a "bone ingrowth" effect into the prosthesis. However, these processes have an unavoidable consequence: a significant reduction in the mechanical strength of the substrate, thus increasing the risk of prosthesis fracture, especially when the prosthesis (such as the femoral stem) is subjected to bending torque or tensile stress. Therefore, reliably and firmly integrating a porous structure with its substrate while ensuring that the mechanical properties of the substrate are not significantly affected becomes a design and manufacturing challenge.

[0008] Comparatively, welding processes have a lower impact on the mechanical properties of the substrate. However, when the porosity of a porous structure is very high (>50%), the interconnected supports are relatively small and weak, resulting in numerous pores between them. Regardless of whether such a high-porosity structure is achieved using metal 3D printing additive manufacturing or sintering, the strength of the substrate structure will be significantly reduced when using penetration welding to connect the porous structure and the substrate under high temperature and pressure conditions.

[0009] For the reasons mentioned above, it is necessary to develop a method that can improve the bonding strength between the porous structure and the substrate, while also avoiding the significant decrease in the mechanical properties of the substrate caused by hot pressing processes (such as penetration welding). Summary of the Invention

[0010] The purpose of this invention is to provide a method and prosthesis for connecting a porous surface structure and a substrate. A polymer material layer is placed within the gap between the porous surface structure and the substrate, allowing for a tight bond between the porous surface structure and the substrate. This ensures the basic strength of the connection structure and improves stress shielding, solving the problem of postoperative osteolysis in existing technologies. Furthermore, this invention can pre-connect a composite material on the substrate. This composite material includes another pre-connected porous structure and an intermediate body. After the pre-connected composite material and the substrate are pre-bonded using various methods (including laser welding, resistance welding, etc.), the substrate with the pre-connected composite material is then tightly bonded to the porous surface structure via the polymer material layer. This prevents relative movement or even detachment between the structure formed by the polymer material layer and the porous structure on its surface and the smooth substrate. Based on the porous structure surface of this invention, the implanted prosthesis can be guaranteed to have excellent bone ingrowth performance, while the strength of the substrate is not substantially affected. Moreover, the optimized stiffness of the overall composite structure reduces the risk of stress shielding.

[0011] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0012] (I) This invention provides a method for preparing a connection structure between a porous surface structure and a substrate, the method comprising:

[0013] At least one pre-connected porous structure is provided on the substrate, and the pre-connected porous structure is pre-connected to the substrate;

[0014] A gap is left between the side of the pre-connected porous structure away from the substrate and the side of the porous surface structure close to the substrate;

[0015] Molten thermoplastic material is placed in the gap; the molten thermoplastic material penetrates into the interior of the porous surface structure and the pre-connected porous structure respectively;

[0016] The solidified thermoplastic material connects the porous surface structure with the pre-connected porous structure, which is located on the surface of the substrate.

[0017] Preferably, the side of the porous surface structure closest to the substrate is referred to as the inner side, and the gap is the pore portion between a spacer layer disposed on the inner side of the porous surface structure and the side of the pre-connected porous structure furthest from the substrate. The spacer layer is used to prevent excessive penetration of thermoplastic materials. Preferably, the spacer layer is a solid structure or a porous structure; the porous surface structure and the spacer layer are integrally formed.

[0018] Preferably, the molten thermoplastic material is formed by injecting molten thermoplastic material into the gap and / or by placing thermoplastic material in the gap and then heating and melting it.

[0019] Preferably, the side of the pre-connected porous structure near the substrate is pre-connected to the side of the substrate near the porous surface structure by laser welding and / or resistance welding.

[0020] Preferably, when resistance welding is used, it further includes:

[0021] At least a portion of the pre-connected porous structure is in direct contact with the substrate. The substrate and the pre-connected porous structure are placed between a first polar electrode and a second polar electrode. The first polar electrode is in conductive contact with the pre-connected porous structure, and the substrate is in conductive contact with the second polar electrode, forming a current loop, so that the contact portion between the pre-connected porous structure and the substrate is resistively welded to the substrate.

[0022] And / or, an intermediate body is provided between the pre-connected porous structure and the substrate, and the intermediate body and the pre-connected porous structure form a pre-connected composite. The pre-connected composite and the substrate are placed between a first polar electrode and a second polar electrode. The first polar electrode is in conductive contact with the pre-connected porous structure and / or the intermediate body, and the substrate is in conductive contact with the second polar electrode, forming a current loop, so that the intermediate body and the substrate are resistively welded, thereby realizing the connection between the pre-connected composite and the substrate.

[0023] Preferably, the pre-connected porous structure in the pre-connected composite is called the first porous structure; the intermediate is a solid structure, or the intermediate is a second porous structure and the porosity of the second porous structure is lower than that of the first porous structure.

[0024] Preferably, the resistance welding is projection welding and / or spot welding.

[0025] Preferably, when the resistance welding is projection welding, the first polarity electrode is a continuous planar electrode or multiple segmented electrode units, and the second polarity electrode is a continuous planar electrode or multiple segmented electrode units; when the resistance welding is spot welding, the first polarity electrode and / or the second polarity electrode are multiple segmented electrode units.

[0026] Preferably, during spot welding resistance welding, the current welding position is moved to the next welding position by moving any one or more of the following components: a first polarity electrode, a second polarity electrode, and an intermediate body and substrate that have been welded at at least one contact position.

[0027] Preferably, when the first polar electrode is divided into multiple electrode units, the electrode units are inserted into the pre-made gaps in the pre-connected porous structure, and the electrode units are close to the intermediate body, so that the inserted electrode units make conductive contact with the intermediate body or make the inserted electrode units make conductive contact with the intermediate body through the pre-connected porous structure.

[0028] Preferably, the electrode unit passes through the surface of the pre-connected porous structure and penetrates into the surface of the intermediate or the interior of the intermediate, so that the inserted electrode unit makes conductive contact with the intermediate.

[0029] Preferably, the electrode unit and the pre-connected porous structure are in a lateral clearance fit, so that the electrode unit and the pre-connected porous structure do not come into contact at all.

[0030] Preferably, multiple electrode units are connected in parallel to another planar electrode and the other planar electrode is connected to the power supply terminal; or, multiple electrode units are connected in parallel and directly connected to the power supply terminal.

[0031] Preferably, the first polar electrode is a flexible electrode. Under pressure, the flexible electrode deforms to match the surface of the pre-connected porous structure, thereby increasing the contact area between the flexible electrode and the surface of the pre-connected porous structure.

[0032] Preferably, the first polarity electrode is a positive electrode and the second polarity electrode is a negative electrode; or, the first polarity electrode is a negative electrode and the second polarity electrode is a positive electrode.

[0033] Preferably, at least a portion of the pores within the pre-connected porous structure are filled with conductive material.

[0034] Preferably, at least a portion of the pores within the pre-connected porous structure are filled with powdered conductive material, filamentous conductive material, or mesh-like conductive material.

[0035] Preferably, at least a portion of the surface of the pre-connected porous structure is covered with a deformable conductive medium in the form of a solid film, filament, or mesh, and the deformable conductive medium is located between the first polar electrode and the pre-connected porous structure; and / or, a solid conductive medium or liquid conductive agent is sprayed between the surface of at least a portion of the pre-connected porous structure and the first polar electrode.

[0036] Preferably, at least a portion of the pores of the pre-connected porous structure are filled with a molten conductive medium, and / or at least a portion of the pores of the pre-connected porous structure contain a conductive medium, which is then molten at high temperature; the melting point of the conductive medium is lower than the melting point of the substrate and / or the melting point of the pre-connected porous structure.

[0037] Preferably, the second polar electrode is a continuous planar electrode; or, the second polar electrode is divided into multiple regions, each matching a different region.

[0038] Preferably, when laser welding is used, the method further includes: an intermediate body is disposed between the pre-connected porous structure and the substrate, and the intermediate body and the pre-connected porous structure form a pre-connected composite; there is at least one pair of contact surfaces between the intermediate body and the substrate; the intermediate body and the substrate are connected and fixed by laser welding at least one pair of contact surfaces between them.

[0039] Preferably, the substrate includes a connecting region that contacts and connects to an intermediate of a pre-connected composite, or contacts and connects to intermediates of multiple pre-connected composites respectively; or, the substrate includes multiple connecting regions that contact and connect to an intermediate of the same pre-connected composite; or, the substrate includes multiple connecting regions, wherein each connecting region contacts and connects to an intermediate of a corresponding pre-connected composite, or each connecting region contacts and connects to intermediates of multiple corresponding pre-connected composites respectively.

[0040] Preferably, when the substrate includes multiple connecting regions, the multiple connecting regions are located on the same plane, or a portion of the connecting regions are not located on the same plane as other connecting regions on the substrate; the multiple connecting regions on the substrate are arranged independently, or at least a portion of the connecting regions on the substrate are interconnected with other connecting regions on the substrate.

[0041] Preferably, at least one pair of contact surfaces between the intermediate and the substrate are welded together, and the pair of welded contact surfaces are referred to as a pair of first contact surfaces; at least one pair of contact surfaces between the intermediate and the substrate are respectively provided with positioning structures, and the pair of contact surfaces respectively provided with positioning structures are referred to as a pair of second contact surfaces; the second contact surfaces respectively provided with positioning structures belong to the first contact surfaces that are welded together; or, the second contact surfaces respectively provided with positioning structures do not belong to the first contact surfaces that are welded together.

[0042] (II) The present invention also provides a method for preparing a connecting structure, the method comprising the following steps: providing at least two pre-connected porous structures and at least two porous surface structures using the method described in (I) above; providing at least two connecting regions on the substrate surface, which are pre-connected to the two pre-connected porous structures respectively; leaving gaps between the side of each pre-connected porous structure away from the substrate and the side of the corresponding porous surface structure near the substrate; placing molten thermoplastic material in all gaps; the molten thermoplastic material penetrating into the interior of the porous surface structure and the matching pre-connected porous structure respectively; and the solidified thermoplastic material connecting the porous surface structure and the pre-connected porous structure, wherein the porous surface structure is located on the surface of the substrate.

[0043] (III) The present invention also provides a method for preparing a connection structure, the method comprising the following steps: providing at least two pre-connected composites using the method in (I) above, namely a first pre-connected composite and a second pre-connected composite; disposing the first pre-connected composite, a substrate, and the second pre-connected composite between a first polar electrode and a second polar electrode; placing the first pre-connected composite between the first polar electrode and the substrate, with an intermediate in the first pre-connected composite in contact with the substrate, and the first polar electrode in conductive contact with the pre-connected porous structure and / or the intermediate in the first pre-connected composite; placing the second pre-connected composite between the second polar electrode and the substrate, with an intermediate in the second pre-connected composite in contact with the substrate, and the second polar electrode in conductive contact with the pre-connected porous structure in the second pre-connected composite. The structure and / or intermediates are electrically connected to form a current loop; the intermediates of the first pre-connected composite and the substrate, and the intermediates of the second pre-connected composite and the substrate are resistance welded to achieve the connection between the pre-connected composite and the substrate; gaps are left between the side of the pre-connected porous structure away from the substrate and the side of the corresponding porous surface structure near the substrate in each pre-connected composite; molten thermoplastic material is placed in all gaps; the molten thermoplastic material penetrates into the interior of the porous surface structure and the pre-connected porous structure in the matching pre-connected composite; the solidified thermoplastic material connects the porous surface structure to the pre-connected porous structure in the corresponding pre-connected composite, with the porous surface structure located on the surface of the substrate.

[0044] Preferably, the method for obtaining the first pre-linked complex using the above method is called the first method, and the method for obtaining the second pre-linked complex using the above method is called the second method. The first method and the second method may be the same or different.

[0045] (iv) The present invention provides a prosthesis with a connecting structure comprising a porous surface structure and a substrate, the substrate being used to form the prosthesis body; at least a portion of the surface of the prosthesis body serves as a connecting region and a pre-connected porous structure is provided on the connecting region for pre-connection with the prosthesis body; a gap is left between the side of the pre-connected porous structure away from the prosthesis body and the side of the porous surface structure close to the prosthesis body, through which molten thermoplastic material in the gap penetrates into the interior of the porous surface structure and the pre-connected porous structure respectively, so that the solidified thermoplastic material connects the porous surface structure and the pre-connected porous structure, the porous surface structure being located in the connecting region of the prosthesis body.

[0046] Preferably, the prosthesis is a joint prosthesis. Preferably, the prosthesis comprises a femoral stem of the hip joint, or an acetabular cup of the hip joint, or a tibial support of the tibial plateau, or a femoral condyle. Preferably, the prosthesis is any one or more of the following: patella, spinal fusion cage, lesser plane intervertebral joint, ankle joint, shoulder joint, elbow joint, finger joint, toe joint, artificial intervertebral disc, temporomandibular joint, wrist joint.

[0047] Preferably, the side of the pre-connected porous structure near the substrate is pre-connected to the side of the substrate near the porous surface structure by laser welding and / or resistance welding.

[0048] Preferably, at least a portion of the pre-connected porous structure is in direct contact with the substrate, and the contact portion between the pre-connected porous structure and the substrate is resistively welded to the substrate; and / or, an intermediate body is provided between the pre-connected porous structure and the substrate, and the intermediate body and the pre-connected porous structure form a pre-connected composite, and the intermediate body and the substrate are resistively welded to achieve the connection between the pre-connected composite and the substrate.

[0049] Preferably, the pre-connected porous structure in the pre-connected composite is referred to as the first porous structure; the intermediate is a solid structure, or the intermediate is a second porous structure and the porosity of the second porous structure is lower than that of the first porous structure. Preferably, the substrate is made of a conductive material, the pre-connected porous structure is made of a conductive material, and the intermediate is made of a conductive material.

[0050] Preferably, the intermediate body comprises an intermediate plate structure.

[0051] Preferably, the intermediate plate structure is provided with a plurality of protrusions, which are located on the side of the intermediate plate structure close to the substrate, and the protrusions of the protrusions are in contact with the substrate.

[0052] Preferably, the intermediate is a second porous structure, which includes multiple protrusions formed on the side of the second porous structure near the substrate, with the protrusions of the protrusions contacting the substrate.

[0053] Preferably, the intermediate body includes a plurality of dispersed protrusions formed on the side of the pre-connected porous structure near the substrate, and the protrusions of the protrusions are in contact with the substrate.

[0054] Preferably, the connection structure includes a plurality of support columns, all or at least part of each support column being located within the pre-connected porous structure.

[0055] Preferably, the support column and the protruding structure of the intermediate body are arranged correspondingly and in contact, or the support column and the protruding structure of the intermediate body are staggered and do not contact each other.

[0056] Preferably, the surface of the support column on the side away from the substrate extends beyond the surface of the pre-connected porous structure; or, the surface of the support column on the side away from the substrate is lower than the surface of the pre-connected porous structure; or, the surface of the support column on the side away from the substrate is flush with the surface of the pre-connected porous structure.

[0057] Preferably, when the support post is a conductor, the support post is connected to the current loop and the support post is in conductive contact with any one or more of the following components: a first polar electrode, a pre-connected porous structure, and an intermediate body.

[0058] Preferably, the support column is an insulator.

[0059] Preferably, the substrate includes a surface bonding layer, which is pre-connected to the substrate body and is located between the intermediate body of the pre-connected composite and the substrate body. The surface bonding layer includes a protruding structure, and the protrusions of the protruding structure of the surface bonding layer contact the intermediate body of the pre-connected composite. Preferably, the surface bonding layer of the substrate is pre-welded to the substrate body. Preferably, the side of the intermediate body near the substrate is planar; or, the protruding structure on the side of the intermediate body near the substrate is offset from the protruding structure of the surface bonding layer.

[0060] Preferably, an intermediate body is provided between the pre-connected porous structure and the substrate, and the intermediate body and the pre-connected porous structure form a pre-connected composite; there is at least one pair of contact surfaces between the intermediate body and the substrate; the intermediate body and the substrate are connected and fixed by laser welding at least one pair of contact surfaces between them.

[0061] Preferably, at least one pair of contact surfaces between the intermediate and the substrate are provided with positioning structures, and the pair of contact surfaces provided with positioning structures are referred to as a pair of second contact surfaces; the second contact surfaces provided with positioning structures belong to the first contact surfaces that are welded together; or, the second contact surfaces provided with positioning structures do not belong to the first contact surfaces that are welded together.

[0062] Preferably, the positioning structure includes: a limiting opening formed on one of any pair of second contact surfaces; and a protrusion formed on the other contact surface of any pair of second contact surfaces and inserted into the limiting opening at the corresponding position.

[0063] Preferably, any pair of second contact surfaces form a positioning structure through matching surface shapes and sizes.

[0064] Preferably, the connection region of the substrate includes a recess formed in the substrate; the pre-connected composite includes an embedded portion embedded in the recess, and an intermediate body located in the embedded portion has at least one pair of contact surfaces between it and the substrate recess; the intermediate body located in the embedded portion and the substrate recess are welded at at least one pair of contact surfaces between them.

[0065] Preferably, the recess of the base has an opening and a top surface opposite the opening; a side edge is provided between the opening and the top surface; the intermediate body located in the embedded portion includes a bottom, and the bottom of the intermediate body is welded to the top surface of the recess of the base; or, the intermediate body located in the embedded portion includes a bottom and a periphery, the bottom of the intermediate body is welded to the top surface of the recess of the base, and / or at least one periphery of the intermediate body is welded to at least one side edge of the recess of the base.

[0066] Preferably, at least one pair of contact surfaces between the intermediate body and the substrate form a positioning structure through mating surfaces; the positioning structure includes: at least one side of the recessed portion of the substrate is a sloped surface, which forms a predetermined angle with the top surface of the recessed portion of the substrate; at least one periphery of the intermediate body corresponding to the at least one side is a sloped surface, which forms a predetermined angle with the bottom of the intermediate body. The preferred angle is an acute angle.

[0067] Preferably, the intermediate of the pre-linked composite is plate-shaped or sheet-shaped.

[0068] Preferably, the substrate is a solid structure, or the substrate is a third porous structure and the porosity of the third porous structure is less than the porosity of the pre-connected porous structure.

[0069] Preferably, the substrate is made by forging, casting, machining, powder metallurgy, or metal injection molding.

[0070] Preferably, the pre-connected porous structure of the pre-connected composite is integrally formed with the intermediate.

[0071] Preferably, the pre-connected porous structure and intermediate of the pre-connected composite are realized by 3D printing additive manufacturing process or vapor deposition process.

[0072] Preferably, the pre-connected porous structure, intermediate body and support column are integrally formed.

[0073] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0074] (1) The present invention manufactures a solid (high density) substrate by forging, casting or machining, or the substrate can be a porous structure, but the density of the porous surface structure is lower than that of the substrate; the present invention adds a polymer material in the connection structure between the porous surface structure and the substrate, which can appropriately reduce the thickness of the substrate layer, ensuring the basic strength of the connection structure and improving the stress shielding phenomenon, thus solving the problem of postoperative osteolysis in the prior art; at the same time, it further sets a spacer layer (such as a porous structure with low porosity or a solid plate) to block the unrestricted penetration of the polymer material, and avoids the polymer material from penetrating beyond the top surface of the connection structure due to continuous penetration during the injection process, so as to form a more aesthetically pleasing connection structure surface.

[0075] (2) The present invention can also pre-set another porous structure on a smooth substrate. After the other porous structure is pre-bonded to the substrate by various methods (including laser welding, resistance welding, etc.), the porous surface structure and the substrate with the other porous structure are tightly connected by a polymer material layer. This can prevent the polymer material layer and the porous structure on its surface from falling off from the smooth substrate, and can also avoid the problem of a significant decrease in the mechanical properties of the substrate caused by hot pressing processes (such as penetration welding processes). Furthermore, when resistance welding (such as projection welding or spot welding) is used to bond another porous structure to the substrate, an intermediate body is designed between the other porous structure and the substrate. This intermediate body can have a higher density than the other porous structure. The other porous structure and the intermediate body are pre-connected into a pre-connected composite body through 3D printing or other processes, so that the pre-connected composite body formed by the other porous structure and the intermediate body can be tightly bonded to the substrate, thereby improving the bonding efficiency between the other porous structure and the substrate and ensuring sufficient welding strength, ultimately ensuring a tight bond between the porous surface structure and the substrate with the pre-connected composite body.

[0076] (3) The processing operation of the present invention is simplified, the manufacturing cost is reduced, and time is saved.

[0077] (4) The present invention utilizes the porous surface structure and the connection structure and method of the substrate to produce various artificial implants, especially orthopedic implants, such as femoral stem, acetabular cup, tibial plateau, femoral condyle, etc., making the main body of the implant easy to process and having high strength. At the same time, the porous surface structure effectively combined with it optimizes the bone ingrowth performance and can also minimize the cross-section of the implant (such as femoral stem). Attached Figure Description

[0078] Figure 1 This is a schematic diagram of the connection structure between the substrate and the porous surface structure in the prior art;

[0079] Figures 2a-2bThis is a schematic diagram of the connection structure between the porous surface structure and the substrate before and after filling in Embodiment 1 of the present invention;

[0080] Figures 3a-3b This is a schematic diagram of the connection structure between the porous surface structure and the substrate before and after filling in Example 2;

[0081] Figures 4a-4b This is a schematic diagram of the connection structure between the porous surface structure and the substrate before and after filling in Example 3;

[0082] Figure 5 This is a schematic diagram of the connection structure between the porous surface structure and the substrate in Example 4;

[0083] Figures 5a-5b for Figure 5 A schematic diagram of the principle of the local structure;

[0084] Figure 6 This is a schematic diagram of the connection structure between the porous surface structure and the substrate in Example 5;

[0085] Figure 7 This is a schematic diagram of the connection structure between the porous surface structure and the substrate in Example 6;

[0086] Figures 8a-8b This is a schematic diagram of the femoral stem of the artificial prosthesis in Example 7;

[0087] Figure 8c For Figure 8a A cross-sectional schematic diagram;

[0088] Figures 9a-9e This is a schematic diagram of the stem housing of the artificial prosthesis in Example 7;

[0089] Figure 10a This is a schematic diagram of the acetabular cup of the artificial prosthesis in Example 8;

[0090] Figure 10b For Figure 10a A partial schematic diagram;

[0091] Figure 11a This is a schematic diagram of the tibial platform of the artificial prosthesis in Example 9;

[0092] Figure 11b For Figure 11a A partial schematic diagram;

[0093] Figure 12a This is a schematic diagram of the femoral condyle of the artificial prosthesis in Example 10;

[0094] Figure 12b For Figure 12a A partial schematic diagram;

[0095] Figure 13a This is a schematic diagram of the connection structure between the pre-connected porous structure and the substrate in Example 11 (the lower surface of the low porosity region does not have protrusions).

[0096] Figure 13b This is a schematic diagram of the connection structure between the pre-connected porous structure and the substrate in Example 11 (the lower surface of the low porosity region has protrusions).

[0097] Figure 14 This is a schematic diagram of the connection structure between the pre-connected porous structure and the substrate in Example 12;

[0098] Figure 15 This is a schematic diagram of the connection structure between the pre-connected porous structure and the substrate in Example 13;

[0099] Figures 16a-16b This is a schematic diagram illustrating the relevant deformations of the connection structure in Example Thirteen;

[0100] Figure 17 This is a schematic diagram of the connection structure between the pre-connected porous structure and the substrate in Example 14;

[0101] Figure 18a This is a schematic diagram of the connection structure between the pre-connected porous structure and the substrate in Example 15;

[0102] Figure 18b This is a schematic diagram of the connection structure between the pre-connected porous structure and the substrate in Example Sixteen;

[0103] Figure 18c This is a schematic diagram of the connection structure between the pre-connected porous structure and the substrate in Example 17;

[0104] Figure 19a This is a schematic diagram of the connection structure between the pre-connected porous structure and the substrate in Example 18;

[0105] Figure 19b This is a schematic diagram of the connection structure between the pre-connected porous structure and the substrate in Example 19;

[0106] Figure 20a This is a schematic diagram of the connection structure between the pre-connected porous structure and the substrate in Example 20;

[0107] Figure 20b This is a schematic diagram of the connection structure between the pre-connected porous structure and the substrate in Example 21;

[0108] Figure 21a This is a schematic diagram of the connection structure between the pre-connected porous structure and the substrate in Example 22;

[0109] Figures 21b-21d This is a schematic diagram of the connection structure between the pre-connected porous structure and the substrate in Example 23;

[0110] Figure 22 This is a schematic diagram of the connection structure between the pre-connected porous structure and the substrate in Example 24;

[0111] Figures 23-24 This is a schematic diagram of the connection structure between the pre-connected porous structure and the substrate in Example 25;

[0112] Figure 25 This is a schematic diagram of the connection structure between the pre-connected porous structure and the substrate in Example 27;

[0113] Figure 26 This is a schematic diagram of the connection structure between the pre-connected porous structure and the substrate in Example 29;

[0114] Figures 27-28 This is a schematic diagram of the connection structure between the pre-connected porous structure and the substrate in Example 30;

[0115] Figure 29 A schematic diagram of the connection between the composite and the substrate in Example 31;

[0116] Figure 30 This is a schematic diagram of the connection between the composite of Example 31 and the base with a recess;

[0117] Figure 31 This is a schematic diagram of the composite and the base recess of Example 31, with corresponding beveled edges on both sides;

[0118] Figure 32 This is a schematic diagram of the composite and the base recess of Example 31, which have a corresponding bevel on one side;

[0119] Figure 33 This is a schematic diagram of the composite and the base recess in Example 31, which have a snap-fit ​​structure on both sides.

[0120] Figure 34 This is a schematic diagram of the composite and the base recess of Example 31 having a snap-fit ​​structure on one side. Detailed Implementation

[0121] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0122] Example 1:

[0123] Figure 2a and Figure 2bThese are schematic diagrams of the porous surface structure and the substrate before and after filling, respectively, in Example 1. Figure 2a The positive X-axis direction represents the right, the negative X-axis direction represents the left, the positive Y-axis represents the top, and the negative Y-axis represents the bottom. The orientation rules in subsequent embodiments are the same as those in this first embodiment, used to more clearly describe the technical solution of the present invention. The above orientation rules are only for illustration and do not affect the orientation in actual applications.

[0124] The base 162 is solid, which is beneficial to the overall strength of the connection structure, such as... Figure 2a and Figure 2b As shown. Alternatively, the substrate may be another porous structure with a porosity less than that of the porous surface structure (not shown). The substrate 162 may be made of metallic material, formed by forging, casting, or other methods, and may be subjected to various machining processes. The porous surface structure 161 comprises numerous staggered supports (or beams), forming multi-directional, regularly or irregularly shaped pores between these supports (or beams). Figure 2a As shown, before filling, the porous surface structure 161 and the substrate 162 are not bonded. At this time, there is a gap between the porous surface structure 161 and the substrate 162. Therefore, in Example 1, the high-temperature molten polymer material 163 is injected into the gap or the polymer material 163 is placed in the gap and then melted at high temperature. After cooling, the polymer material 163 forms a tight bond with the lower part of the porous surface structure 161.

[0125] In this embodiment, a polymer material is added as an intermediate layer to the connection structure between the porous surface structure and the substrate. This not only ensures the basic strength of the connection structure but also improves the stress shielding effect. The stress shielding effect refers to the phenomenon where, when two materials with different elastic moduli are subjected to stress together, the material with the larger elastic modulus bears more stress. When the elastic modulus of the substrate is much larger than that of the bone, the bone bears less stress, which can lead to long-term stress shielding and osteolysis after surgery in severe cases. Because this invention incorporates a polymer material with an elastic modulus lower than that of the substrate, the stress shielding effect is correspondingly improved.

[0126] Example 2:

[0127] Regarding Embodiment 1, the above solution has a drawback: because the scaffold (or beam) of the porous surface structure 161 forms some multi-directional, regularly or irregularly shaped pores, when the polymer material 163 is injected to fill the pores of the porous surface structure 161, some of the polymer material may continue to penetrate until it exceeds the top of the porous surface structure 161, which will greatly affect the appearance and other performance characteristics (such as bone ingrowth) of the porous surface structure 161.

[0128] To address the aforementioned issues, the connecting structure in this second embodiment comprises a porous surface structure in a high-porosity region (also referred to as the first porous structure 171), a second porous structure 172 in a low-porosity region (serving as a spacer layer), and a substrate 173. The second porous structure 172 is located between the first porous structure 171 and the substrate 173. Figure 3a and Figure 3b As shown in the figure.

[0129] For example, the first porous structure 171 and / or the second porous structure 172 comprises numerous staggered supports (or beams) forming multi-directional, regularly or irregularly shaped pores. The porosity of the first porous structure 171 is denoted as a%, and the porosity of the second porous structure 172 is denoted as b%, where a% > b%. Therefore, when the spacer layer uses the second porous structure 172, compared to the first porous structure 171 constituting the porous surface structure, the second porous structure 172 has a higher density, manifested as coarser supports (beams) and / or lower porosity in the second porous structure 172.

[0130] like Figure 3a The diagram shows a schematic of the porous surface structure and substrate before filling in Embodiment 2 of the present invention. Optionally, the first porous structure 171 and the second porous structure 172 are integrally formed, for example, pre-formed using 3D printing additive manufacturing process or vapor deposition process before filling. Before filling, the integral structure formed by the first porous structure 171 in the high porosity region and the second porous structure 172 in the low porosity region and the substrate 172 have not yet been connected, and there are gaps between the integral structure and the substrate 173. Therefore, in Embodiment 2, by injecting the high-temperature molten polymer material 174 into the gaps or by placing the polymer material 174 in the gaps and then melting it at high temperature, the polymer material 174, after cooling, forms a tight bond with at least a portion of the second porous structure 172, while the polymer material 174 wraps around the substrate 173 (although the bond between the polymer material 174 and the substrate 173 is not strong), the connection between the integral structure formed by the first porous structure 171 and the second porous structure 172 and the substrate is achieved, such as... Figure 3b As shown; when the substrate 173 does not form an encapsulation, the following solution from Example 4 needs to be adopted ( Figure 5 ).

[0131] To prevent the polymer material from continuously permeating beyond the top of the first porous structure 171 during injection, and to avoid the difficulty in determining the permeation cutoff point, this embodiment employs a second porous structure 172 in the low-porosity region to block unrestricted polymer material permeation. Specifically, it is necessary to ensure that the staggered arrangement of supports (or beams) within the second porous structure 172 can effectively block the polymer material, thereby separating it from the high-porosity region of the first porous structure 171. Thus, this embodiment ultimately results in a first porous structure 171 with a relatively aesthetically pleasing surface and sufficient porosity.

[0132] Meanwhile, by adding a polymer material as an intermediate layer to the connection structure between the porous surface structure and the substrate, this invention can appropriately reduce the thickness of the substrate layer. This ensures the basic strength of the connection structure and improves the stress shielding effect. The stress shielding effect refers to the phenomenon where, when two materials with different elastic moduli are subjected to stress together, the material with the larger elastic modulus bears more stress. When the elastic modulus of the substrate is much larger than that of the bone, the bone bears less stress, which can lead to long-term stress shielding and osteolysis after surgery in severe cases. Because this invention incorporates a polymer material with an elastic modulus lower than that of the substrate, the stress shielding effect is correspondingly improved.

[0133] It is worth noting that in this second embodiment, the staggered supports (or beams) in the second porous structure 172 should be designed to create a essentially leak-proof porous structure by considering factors such as shape, porosity, and the amount of polymer material injected. Generally, the smaller the porosity, the greater the likelihood of forming a closed, leak-proof spacer layer. Therefore, this invention only needs to ensure that the second porous structure 172 can prevent polymer material from penetrating into the first porous structure 171; the porosity and specific arrangement requirements of the second porous structure 172 are not limited.

[0134] Example 3:

[0135] As a variation of Example 2, such as Figure 4a and Figure 4b As shown, in this embodiment three, a solid, non-porous spacer plate 182 is used to replace the second porous structure 172 in the low-porosity region of embodiment two. That is, when the porosity of the second porous structure in embodiment two is zero, it becomes the non-porous spacer plate 182 in embodiment three. Similarly, the porous surface structure 181 in this embodiment three includes numerous staggered supports (or beams), which form multi-directional, regularly or irregularly shaped pores between these supports (or beams).

[0136] In some examples, the non-porous spacer 182 can be positioned at any cross-sectional location between the top and bottom of the porous surface structure 181.

[0137] For example, the direction in which the non-porous spacer 182 is embedded in the porous surface structure 181 (e.g., embedded parallel to the top surface of the substrate 183 or at a certain angle to the top surface of the substrate 183, etc.) and the shape of the non-porous spacer 182 itself (e.g., planar structure, arc-shaped structure, arbitrary curved surface structure, etc.) are not limited in this invention, as long as the non-porous spacer 182 can effectively prevent the polymer material 184 from penetrating into the porous surface structure 181 above the non-porous spacer 182. In this way, the porous surface structure 181 is not blocked by the polymer.

[0138] Polymer material 184 is injected into the voids within the porous surface structure between the non-porous spacer 182 and the substrate 183. After cooling, the polymer material 184 is tightly bonded to this portion of the porous surface structure. Optionally, the porous surface structure 181 and the non-porous spacer 182 are integrally formed structures, for example, pre-formed using 3D printing additive manufacturing processes or vapor deposition processes before filling.

[0139] Example 4:

[0140] In the second embodiment described above, a polymer material 174 is filled between the second porous structure 172 and the substrate 173, and the polymer material 174 is connected to a portion of the second porous structure 172. Similarly, in the third embodiment described above, a polymer material 184 is filled between the porous surface structure between the non-porous spacer 182 and the substrate 183. When the substrate is a porous structure, at least a portion of the polymer material will penetrate into the porous structure within the substrate, thus connecting the substrate and the porous surface structure. However, when the substrate in the above embodiments is a smooth, non-porous structure such as a titanium alloy, it is difficult to create a porous structure on the substrate surface itself. Therefore, a tight bond cannot be formed between the cooled polymer material and the substrate, especially when the former does not encapsulate the latter. This can easily lead to the polymer material and the porous structure above it detaching from the substrate.

[0141] To achieve a tight bond between the polymer material and the substrate, and to prevent detachment of the polymer material and the porous structure above it from the substrate, this embodiment four adopts the following solution: a pre-connected porous structure 192 is provided at the top of the substrate 193. The pre-connected porous structure 192 is then effectively bonded to the substrate 193 using various methods (including laser welding, resistance welding, etc.). Figure 5As shown. For example, when using resistance welding to bond the pre-connected porous structure 192 to the substrate 193, the pre-connected porous structure 1922 can be directly contacted with the substrate 203 for resistance welding, or the pre-connected porous structure 192 can be bonded to the substrate 193 through an intermediate 196 using resistance welding.

[0142] In a specific example, such as Figure 5 (A schematic diagram after resistance welding is completed) and Figure 5a As shown in the schematic diagram of the resistance welding process, the porous structure of the pre-connected porous structure 192 comprises numerous staggered supports (or beams), forming multi-directional, regularly or irregularly shaped pores between these supports (or beams). An intermediate body 196 is located between the pre-connected porous structure 192 and the substrate 193. Optionally, the intermediate body 196 is a non-porous base plate, i.e., a solid base plate, as illustrated. Both the pre-connected porous structure 192 and the intermediate body 196 are made of conductive materials (such as metal). The pre-connected porous structure 192 and the intermediate body 196 are integrally formed, for example, through 3D printing additive manufacturing processes or vapor deposition processes. For example, the substrate 193 is solid, which is beneficial to the overall strength of the connected structure. The substrate 193 can be made of conductive materials (such as metal), formed by various methods such as forging and casting, and can be subjected to various machining processes.

[0143] like Figure 5a As shown, the pre-connected porous structure 192 and the intermediate body 196 are pre-connected to form a composite 2A, and the intermediate body 196 and the substrate 193 are effectively bonded by resistance welding, thus connecting the composite 2A and the substrate 193. The principle of resistance welding is to use a method that presses two workpieces between two electrodes and uses the resistance heat generated by the flow of current through the contact surface and adjacent areas between the two workpieces to form an effective bond between the metal workpieces, thereby connecting the porous structure and the substrate. The resistance welding method includes spot welding and / or projection welding, etc. This embodiment focuses on illustrating the connection of the intermediate body 196 and the substrate 193 using a projection welding resistance welding method.

[0144] like Figure 5 As shown, in this fourth embodiment, the intermediate 196 between the pre-connected porous structure 192 and the substrate 193 (such as...) Figure 5The non-porous base plate 196) is bonded to the substrate 193 using a projection welding resistance welding method, forming a bonding interface 19a between the two. Then, a certain gap is left between the pre-connected porous structure 192 and the porous surface structure 191 (for bone ingrowth) above it. A high-temperature molten polymer material is injected into this gap, simultaneously penetrating into both the porous surface structure 191 and the pre-connected porous structure 192. Alternatively, polymer material can be placed in the gap and then heated to melt, allowing it to simultaneously penetrate into the porous structures of both the porous surface structure 191 and the pre-connected porous structure 192, ultimately forming a polymer material interlayer 194. At this point, the polymer material interlayer 194 is tightly bonded to both the porous surface structure 191 and the pre-connected porous structure 1922, thereby achieving a tight bond between the porous surface structure 191 and the substrate 193. Figure 5 As shown.

[0145] This example prevents the polymer material and the porous structure above it from detaching from the substrate. Furthermore, by adding an intermediate polymer material to the connection structure between the porous surface structure and the substrate, the thickness of the substrate layer can be appropriately reduced. This ensures the basic strength of the connection structure and improves stress shielding. Stress shielding refers to the phenomenon where, when two materials with different elastic moduli are subjected to stress together, the material with the larger elastic modulus bears more stress. When the elastic modulus of the substrate is much larger than that of the bone, the bone bears less stress, which can lead to postoperative osteolysis in severe cases. Because this invention incorporates a polymer material with an elastic modulus lower than that of the substrate, the stress shielding effect is correspondingly improved.

[0146] In this invention, the pre-connected porous structure 192 and the porous surface structure 191 are independent components. The polymer material intermediate layer 194 fills at least a portion of the pores in the porous surface structure 191 and at least a portion of the pores in the pre-connected porous structure 192. Furthermore, this invention does not limit the method for effectively combining the pre-connected porous structure 192 and the substrate 193, as long as the connection between the two can be achieved.

[0147] Regarding the principle of projection welding resistance welding in this example, specifically: Figure 5aAs shown, at least a portion of the top of the pre-connected porous structure 192 contacts the positive electrode 24. Since the pre-connected porous structure 192 is pre-connected to the intermediate body 196, at least a portion of the bottom of the pre-connected porous structure 192 contacts the top of the intermediate body 196. A plurality of protrusions 221 are pre-fabricated on the bottom of the intermediate body 196, which contact the top of the substrate 193, and the bottom of the substrate 193 contacts the negative electrode 25. The protrusions 221 protrude towards the substrate 193. Preferably, the locations of the protrusions 221 correspond to the locations where the bottom of the pre-connected porous structure 192 contacts the top of the intermediate body 196 and their adjacent areas. The composite 2A formed by the pre-connected porous structure 192 and the intermediate body 196, and the substrate 193, are pressed between the positive electrode 24 and the negative electrode 25. When an electric current is applied, it flows through the pre-connected porous structure 192, the intermediate body 196, and up to the contact surface and adjacent area of ​​the protrusion structure 221 and the top of the substrate 193. Due to the contact resistance, resistance heat is generated, which heats the protrusion structure 221 and the top of the substrate 193 to a molten or plastic state. This causes the protrusion structure 221 of the intermediate body 196 and the top of the substrate 193 to form a metal bond, ultimately achieving the solid connection between the intermediate body 196 and the substrate 193. As a result, the composite 2A formed by the pre-connected porous structure 192 and the intermediate body 196 is tightly bonded to the substrate 193.

[0148] Because the bottom of the intermediate body 196 has multiple protrusions 221, these protrusions 221 come into contact with the top surface of the substrate 193, creating contact resistance. As current flows through them, resistive heat is generated, and these contact points between the protrusions 221 and the substrate 193 form solder joints. Contact resistance refers to the resistance generated when current flows between two independent workpieces in contact, and the resistive heat Q is proportional to IR. 2 R is the contact resistance, and I is the current passing through the workpiece. The greater the current, the greater the contact resistance, and the greater the resistance heat value; conversely, the smaller the resistance heat value, the less the current.

[0149] Based on the above, in this example, the intermediate body 196 increases its contact resistance with the substrate 193 through a raised structure (such as a protrusion), generating sufficient resistive heat, thus ensuring sufficient welding strength between the raised structure 221 and the substrate 193. Preferably, the substrate 193 is made of titanium alloy. For example, the shape of the raised structure 221 of the intermediate body 196 can be spherical, arc-shaped, annular, or elongated, etc. This embodiment does not specifically limit this, nor is it limited to other examples, such as... Figure 5bAs shown, the intermediate body 196 may have various protrusions or textures to reduce the contact area and increase the contact resistance, thereby correspondingly increasing the bonding efficiency between it and the substrate and improving the welding strength between the intermediate body and the substrate. For example, the positive electrode 24 and the negative electrode 25 are made of conductive material (such as metal); the top of the negative electrode 25 is in close contact with the bottom of the substrate 193, and the bottom of the positive electrode 24 is in close contact with the top of the pre-connected porous structure 192. The contact surfaces can be planar, arc-shaped, or curved, etc. The present invention does not specifically limit the shape, size, etc. of the contact surfaces and can design them according to actual application conditions.

[0150] Therefore, by adding an intermediate between the pre-connected porous structure and the substrate, and using a resistance welding method (e.g., projection welding) to weld the intermediate to the composite formed by the pre-connected porous structure and the substrate, a high bonding efficiency (e.g., 70%~80%) can be ensured even when the porosity of the pre-connected porous structure is very high (>50%). This is higher than the bonding efficiency and greater welding strength achieved by resistance welding that directly contacts the porous structure and the substrate. The positive electrode 24 and negative electrode 25 in this embodiment are also interchangeable, and this extension method is also applicable to subsequent embodiments, which will not be elaborated upon further.

[0151] It is worth noting that when the present invention uses resistance welding to bond the pre-connected porous structure 192 to the substrate through an intermediate, it is not limited to the resistance welding method described in this example. It can also refer to the bonding method of porous surface structure to substrate in the following Examples 11 to 30 and their variations. In this case, the pre-connected porous structure 192 is equivalent to the porous surface structure described in the following Examples 11 to 30 and their variations.

[0152] Example 5:

[0153] Referring to the improvement principle of Embodiment 1 in Embodiment 2 of the present invention, Embodiment 5 makes the same improvement to Embodiment 4, as follows: Figure 6 As shown, in this fifth embodiment, a spacer layer is added between the porous surface structure 201 and the pre-connected porous structure 205. This spacer layer is a second porous structure 202 in a low-porosity region, used to prevent polymer materials from permeating out of a designated location. The porous surface structure 201 is a porous structure in a high-porosity region, also referred to as the first porous structure 201. The second porous structure 202 and the porous surface structure 201 are a composite structure integrally manufactured, which can be achieved through methods such as 3D printing / vapor deposition.

[0154] For example, both the porous surface structure 201 and the porous structure 202 contain numerous staggered supports (or beams), forming multi-directional, regularly shaped or irregularly shaped pores between these supports (or beams). The porosity of the porous surface structure 201 is denoted as a%, and the porosity of the second porous structure 201 is denoted as b%, where a% > b%. Therefore, compared to the porous surface structure 201 constituting the porous surface structure, when the spacer layer uses the second porous structure 202, the second porous structure 202 has a higher density, manifested as coarser supports (beams) and / or lower porosity. Further extending this embodiment, since this embodiment uses the second porous structure 202 in a low-porosity region for blocking, regardless of the range of the porosity b% of the second porous structure 202, it is necessary to ensure that at least some of the staggered supports (or beams) within the second porous structure 202 can block the polymer material.

[0155] In this fifth embodiment, a pre-connected porous structure 205 is provided at the top of the substrate 203. First, the pre-connected porous structure 205 is effectively bonded to the substrate 203 using various methods (including laser welding, resistance welding, etc.). Figure 6 As shown. When resistance welding is used to combine the pre-connected porous structure 205 with the substrate 203, the pre-connected porous structure 205 and the substrate 203 can be directly contacted for resistance welding, or the pre-connected porous structure 205 can be combined with the substrate 203 through the intermediate body 206 using resistance welding.

[0156] like Figure 6 As shown, in this fifth embodiment, an intermediate 206 (such as a pre-connected porous structure 205 and a substrate 203) is used between the pre-connected porous structure 205 and the substrate 203. Figure 6The non-porous base plate 206 is used to bond the pre-connected porous structure 205 to the substrate 203 via projection welding resistance welding, forming a bonding interface 20a between them. Then, a certain gap is left between the pre-connected porous structure 205 and the porous surface structure 201 above it, and a high-temperature molten polymer material is injected into this gap. Because a second porous structure 202 is used to separate the porous surface structure 201 and the pre-connected porous structure 205, it can prevent the polymer material from penetrating beyond the top of the porous surface structure 201 during injection. Therefore, the injected polymer material ultimately penetrates into the gap between the second porous structure 202 and the pre-connected porous structure 205, ultimately forming a polymer material intermediate layer 204. Therefore, in this example, the porous surface structure 201, serving as the porous surface structure, is tightly bonded to the substrate 203. This example can prevent the composite formed by the polymer material and the porous structure above it from detaching from the substrate. In addition, by adding a polymer material as an intermediate layer to the connection structure between the porous surface structure and the substrate, the thickness of the substrate layer can be appropriately reduced. This can ensure the basic strength of the connection structure and improve the stress shielding phenomenon. For details, please refer to Embodiment 4 above, which will not be repeated here.

[0157] It should be noted that the pre-connected porous structure 205 and the porous surface structure 201 are independent components. The polymer material intermediate layer 204 fills at least a portion of the pores in the second porous structure 202 and at least a portion of the pores in the pre-connected porous structure 205. Furthermore, the present invention does not limit the method for effectively combining the pre-connected porous structure 205 and the substrate 203, as long as the connection between the two can be achieved.

[0158] In addition, when the pre-connected porous structure 192 is bonded to the substrate by resistance welding in this embodiment five, the bonding method of porous surface structure to substrate in the following embodiments eleven to thirties and their variations can also be referred to. In this case, the pre-connected porous structure 192 is equivalent to the porous surface structure in the following embodiments eleven to thirties and their variations.

[0159] Example 6:

[0160] As a variation of Example 5, such as Figure 7As shown, in this sixth embodiment, a solid non-porous spacer 212 is used to replace the second porous structure 202 in the low-porosity region of the above embodiment four. That is, when the porosity of the second porous structure 202 in embodiment five is zero, it becomes the non-porous spacer 212 in embodiment six. Other contents of this embodiment (such as the substrate 213, the porous surface structure 211 above the non-porous spacer 212, the polymer material intermediate layer 214, the pre-connected porous structure 215 below the polymer material intermediate layer 214, the intermediate body 216, and the connecting interface 21a, etc.) can refer to embodiment five above, and will not be repeated here.

[0161] Example 7:

[0162] like Figures 8a-8c As shown, this embodiment seven provides an artificial implant prosthesis, preferably an orthopedic prosthesis; any one or more connection structures and methods from embodiments one to six and their respective variations can be used. The prosthesis body 1 corresponds to the substrate in the connecting structure. At least a portion of the surface of the prosthesis body 1 serves as a connecting region and is connected to the porous surface structure. For example, it is connected to the substrate (e.g., substrate 162 in Example 1, substrate 173 in Example 2, substrate 184 in Example 3) through a polymer material (e.g., polymer material 163 in Example 1, substrate 173 in Example 2, substrate 183 in Example 3, etc.), or through a single pre-connected porous structure, or through a pre-connected composite of the pre-connected porous structure and an intermediate, and a polymer material layer (e.g., pre-connected porous structure 192, intermediate 196, and polymer material layer 194 in Example 4, or pre-connected porous structure 205, intermediate 206, and polymer material layer 204 in Example 5, etc.) and the porous surface structure, thus achieving the connection between the porous surface structure and the substrate, forming a surface cover over the connecting region on the prosthesis.

[0163] This invention, in conjunction with the structures and methods of Embodiments 1 to 6 or their variations, provides a prosthesis shell with an outer layer of porous surface structure and an inner layer of polymer material, or a combination of a pre-connected porous structure and polymer material, or a pre-connected composite (a composite of a pre-connected porous structure and an intermediate) and polymer material. This shell is then fixedly connected to the connection area of ​​the prosthesis body using various methods, achieving the connection between the porous surface structure and the prosthesis body. This forms a surface cover over the connection area of ​​the prosthesis body, enabling its application in various other types of orthopedic prostheses, artificial joints, and other artificial implants, such as femoral stems, acetabular cups, femoral condyles, and tibial plateaus. Specific details are described in the subsequent embodiments.

[0164] Let's take an artificial hip joint as an example. An artificial hip joint includes a femoral stem, femoral head (not shown in the figure), acetabular cup, and liner (not shown in the figure), all of which are prostheses made of medical materials that can be implanted in the human body, such as metal materials like titanium alloy, cobalt-chromium-molybdenum alloy, and stainless steel, polymers like ultra-high molecular weight polyethylene, ceramics, etc., and is not limited to these.

[0165] The femoral stem 3 ( Figures 8a-8c The device comprises a head 301, a neck 302, and a stem 303, which can be integral or assembled. The lower part of the stem 303 is inserted into the femoral medullary cavity. Preferably, the upper surface of the stem 303 has a porous structure; the lower part of the stem 303 has a smooth surface and may have longitudinal grooves. For example, the acetabular cup is a partially spherical (e.g., hemispherical) dome-shaped structure, fixedly connected to the acetabular fossa; the outer peripheral surface of the acetabular cup preferably uses a porous structure.

[0166] To accelerate or enhance the bonding between bone tissue and the porous prosthesis surface, any prosthesis (also applicable to artificial joints in subsequent embodiments) may have a coating such as hydroxyapatite (HA) formed on its surface in contact with bone tissue; or materials such as gel / collagen may be used as carriers for implanted cells, growth factors, etc., and attached to the porous surface of the prosthesis; or an antibacterial coating (such as antibiotics / silver ions, etc.) may be formed.

[0167] The femoral stem 3 can use the structure and method of Embodiments 1 to 6 or their variations, which will not be repeated here. Please refer to the corresponding embodiments for details. The stem body 303 of the femoral stem 3 corresponds to the substrate in the connecting structure; it comprises an intermediate connector (such as a polymer material, or a combination of a pre-connected porous structure and a polymer material, or a combination of a pre-connected composite and a polymer material, etc., which needs to be determined according to different embodiments), and a combination of porous surface structures to form the stem body shell 2, which covers the connecting area of ​​the stem body 303a (upper part) and connects to the substrate, thereby realizing the connection between the porous surface structure 201 and the substrate, forming a cover over the connecting area, resulting in a porous structure on the femoral stem body 303.

[0168] In some examples, the handle body 303a is made by forging, casting, or machining, and is preferably a solid structure for ease of processing and high strength; or the handle body 303a may also be a high-density porous structure. In a specific example, such as... Figure 8c The diagram corresponds to the example shown in Embodiment 1 above. Figure 2a , Figure 2bThe inner stem 303 corresponds to the base in the connecting structure, and the outer porous structure 201 corresponds to the porous surface structure of the connecting structure. A polymer material layer exists between the stem 303 and the porous structure 201. Because the polymer material encapsulates the stem 303, even if the polymer material and stem 303 are not strongly bonded, it does not affect the performance of the femoral stem 3. This example, by adding an intermediate polymer material to the connecting structure between the porous surface structure and the base, can appropriately reduce the thickness of the base layer. This ensures the basic strength of the connecting structure and improves the stress shielding effect. The stress shielding effect refers to the fact that when two materials with different elastic moduli are subjected to force together, the material with the larger elastic modulus will bear more stress. When the elastic modulus of the base is much larger than that of the bone, the bone bears less stress, which can lead to postoperative osteolysis in severe cases. Because this invention incorporates a polymer material with an elastic modulus smaller than that of the base, the stress shielding effect is correspondingly improved. Other aspects of this invention regarding the femoral stem applicable to Embodiment 1 are not elaborated here.

[0169] In a specific example, the upper part of the stem body 303a of the femoral stem 3 is provided with a connecting area, including the inner, posterior, and lateral sides of the upper part of the stem body 303a. Figure 8b ), front side ( Figure 8a The surface of (e.g.) Figures 9a-9e As shown, the handle housing 2 comprises two housing pieces. One housing piece 2-1 corresponds to a portion of the inner surface 01, the rear surface 02, and a portion of the outer surface 03 of the upper part of the handle body 303a. The other housing piece 2-2 corresponds to the remaining portion of the inner surface 01, the front surface 04, and the remaining portion of the outer surface 03 of the upper part of the handle body 303a. After the two housing pieces are joined together, they contact and weld to the corresponding positions of the connection area on the upper part of the handle body. The inner layer of each housing piece is an intermediate body 202, and the outer layer is wholly or mostly a porous surface structure 201.

[0170] like Figure 9d and Figure 9e As shown, the two shell sheets can be symmetrical (or staggered and intersecting, not shown in the figure). For example, after molding and joining, the adjacent edges of the two shell sheets can be separated without connection. Alternatively, during molding, the adjacent edges on one side of the two shell sheets (such as the outer side 03) can be connected, and can remain connected even with a slight bend near the adjacent edges (to allow the two shell sheets to join). Or, the adjacent edges of the two shell sheets can be separated during molding, but after joining, the adjacent edges on each side are connected (e.g., by welding or using connectors or other connection methods). The adjacent edges refer to the edges adjacent to each other after the two shell sheets are joined. The connection of adjacent edges can be achieved by connecting the intermediate body of the inner layer and / or the porous surface structure of the outer layer of each shell sheet.

[0171] Example 8:

[0172] In this embodiment, the porous structure of the outer peripheral surface of the acetabular cup 300a can be implemented similarly using the structure and method of Embodiments 1 to 6 or their variations.

[0173] In a specific example, such as Figure 10a and Figure 10b As shown, this embodiment corresponds to the fourth embodiment described above. Figure 5 The outer shell of the acetabular cup has a cup body corresponding to the base 3-3 in the connecting structure. It includes a pre-connected composite (a composite of a pre-connected porous structure and an intermediate) and a polymer material as intermediate connectors, as well as a porous surface structure 3-1. This composite is formed on the outside of the cup body 3-3 and covers the connecting area of ​​the cup body. It is connected to the base 3-3, thereby realizing the connection between the porous surface structure 3-1 and the base 3-3, forming a cover on the connecting area of ​​the cup body, and obtaining a porous structure on the outer peripheral surface of the acetabular cup.

[0174] The cup body of the acetabular cup is adapted to the entire assembly at the contact and connection points. Specifically, another pre-connected porous structure 3-2 is provided between the porous surface structure 3-1 and the substrate 3-3. First, the pre-connected porous structure 3-2 is effectively combined with the substrate 3-3. Then, a high-temperature molten polymer material 3-5 is injected into the gap between the pre-connected porous structure 3-2 and the porous surface structure 3-1. The polymer material 3-5 is used to tightly combine the porous surface structure 3-1 and the pre-connected porous structure 3-2, thereby achieving a tight connection between the porous surface structure 3-1 and the substrate 3-3. The pre-connected porous structure 3-2 and the substrate 3-3 can be effectively combined by various methods (including laser welding, resistance welding, etc.), such as the resistance welding method in 10b in which the non-porous base plate 3-4 is used as an intermediate in the pre-connected composite. Figure 10a and Figure 10b Corresponding to the above Figure 5 Example 4.

[0175] In some examples, the body of the acetabular cup is made by forging, casting, or machining, preferably a solid structure for ease of processing and high strength; or the body can be a high-density porous structure. When the body of the acetabular cup is connected to the porous surface structure via a pre-connected composite formed by a pre-connected porous structure and an intermediate body, and a polymer material layer, the intermediate body can be solid or a porous structure with a higher density than the pre-connected porous structure. The intermediate body and the pre-connected porous structure in the pre-connected composite are preferably realized using 3D printing additive manufacturing, which can effectively form pores that meet design requirements. Specific details regarding the application of the acetabular cup to other embodiments of the present invention are not elaborated here.

[0176] In a specific example, the entire outer surface of the cup body can be considered as a connecting region. A single assembly is placed in contact with it and connected through its contained polymer material layer or a combination of a polymer material layer and a pre-connected composite in the connecting region. Alternatively, the entire outer surface of the cup body can be divided into multiple independent connecting regions. Multiple assemblies (each can be sheet-like or other shapes adapted to the dome shell) are in contact with these connecting regions respectively and connected through their respective polymer material layers or combinations of polymer material layers and pre-connected composites in these connecting regions. Each assembly has an inner layer consisting of a single polymer material layer or a combination of a polymer material layer and a pre-connected composite, while its outer layer is wholly or mostly porous.

[0177] Example 9:

[0178] The proximal tibia and distal femur form the knee joint. The surface where the tibia and distal femur meet is called the tibial plateau, a crucial load-bearing structure of the knee joint. In implanted prostheses, the component replacing the femoral bone is called the femoral condyle, and the component replacing the tibial bone is called the tibial plateau. A polyethylene spacer exists between the femoral condyle and the tibial plateau to reduce wear and restore knee joint function.

[0179] like Figure 11a and Figure 11b As shown, the tibial plateau 300b has a T-shaped structure, comprising an upper tibial support 300-1 and a lower support portion 300-2. The lower surface of the tibial plateau 300b uses a porous structure, which increases roughness and induces osteoblast bone ingrowth, thereby effectively connecting and fixing the tibial plateau prosthesis to the human tibia, replacing the damaged or diseased tibial surface, and forming good long-term biological fixation to withstand human pressure loads and meet the requirements of sports and wear resistance. The porous structure of the lower surface of the tibial plateau 300b can be similarly implemented using the structures and methods of Embodiments 1 to 6 or their variations.

[0180] In a specific example, the lower surface of the tibial support 300-1 corresponds to the porous surface structure 33-1 of the connecting structure, and the upper end of the tibial support 300-1 corresponds to the inner base 33-3 of the connecting structure; it also includes an intermediate connector (such as a polymer material or a combination of a pre-connected porous structure and a polymer material, or a combination of a pre-connected composite and a polymer material, etc., which needs to be determined according to different embodiments), such as Figure 11a and Figure 11bAs shown in the diagram. Specifically, another pre-connected porous structure 33-2 is also provided between the porous surface structure 33-1 and the substrate 33-3. First, the pre-connected porous structure 33-2 is effectively bonded to the substrate 33-3. Then, a high-temperature molten polymer material 33-5 is injected into the gap between the pre-connected porous structure 33-2 and the porous surface structure 33-1, or the polymer material 33-5 is provided and then heated to melt. The polymer material 33-5 is used to tightly bond the porous surface structure 33-1 and the pre-connected porous structure 33-2, thereby achieving a tight connection between the porous surface structure 33-1 and the substrate 33-3. The pre-connected porous structure 33-2 and the substrate 33-3 can be effectively bonded by various methods (including laser welding, resistance welding, etc.), for example... Figure 11b The resistance welding method described herein utilizes a non-porous base plate 33-4 as an intermediate in a pre-connected composite. In this example, the composite structure consisting of a porous surface structure and an intermediate connector is formed at the lower end of the tibial support and covers the connection area of ​​the tibial support. Specific details regarding the applicability of the tibial platform to other embodiments are not elaborated here.

[0181] Example 10:

[0182] An artificial knee joint prosthesis includes a femoral condyle, a tibial support, a liner positioned between the two, and a patellar prosthesis. The femoral condyle connects to the distal femur, and the tibial support connects to the proximal tibia. The liner component connects to the tibial support component, and the femoral condyle contacts the liner. The lower part of the liner contacts the upper surface of the tibial plateau, and the lateral convex surface of the femoral condyle contacts the upper part of the liner and the articular surface of the patellar prosthesis, allowing for flexion, extension, sliding, and rotation within a specified range.

[0183] The convex surface of the femoral condyle 300c body is typically very smooth to reduce wear between it and the liner. The concave surface of the femoral condyle body matches and contacts the osteotomy section formed at the distal end of the femur. Therefore, it is preferable to form a porous structure on the concave surface of the femoral condyle body (such as the medial condyle fixation surface) to facilitate bone ingrowth, achieve a tight bond between the prosthesis and bone tissue, and reduce the risk of postoperative loosening of the prosthesis leading to joint replacement surgery failure. In this embodiment, the concave surface of the femoral condyle 300c uses a porous structure, which increases roughness to enhance the initial postoperative stability of the prosthesis and promotes bone ingrowth, thereby effectively connecting and fixing the femoral condyle prosthesis to the human femoral condyle. The tibial liner is located between the femoral condyle prosthesis and the tibial plateau prosthesis, bearing the pressure load of the human body and meeting the requirements of joint kinematics and wear resistance. The porous structure (i.e., porous surface structure) on the inner surface of the femoral condyle 300c can be similarly implemented using the structures and methods of Embodiments 1 to 6 or their variations.

[0184] In a specific example, on the inner surface of the femoral condyle 300c, from the outside to the inside, there are a porous surface structure 333-1 with corresponding connecting structures, an intermediate connector (as shown in the figure, the composite formed by the pre-connected porous structure 333-2 and the non-porous base plate 333-4, and the polymer material layer 333-5), and a substrate 333-3, as shown in the figure. Figure 12a and Figure 12b As shown in the figure. Among them, the medial condyle of the femoral condyle 300c corresponds to the base 333-3 of the connecting structure, and the medial condyle fixation surface of the femoral condyle 300c uses a porous surface structure 333-1. Specifically, another pre-connected porous structure 333-2 is provided between the porous surface structure 333-1 and the substrate 333-3. First, the pre-connected porous structure 333-2 is effectively bonded to the substrate 333-3. Then, a high-temperature molten polymer material 333-5 is injected into the gap between the pre-connected porous structure 333-2 and the porous surface structure 333-1, or polymer material 333-5 is provided and then heated to melt. The polymer material 333-5 is used to tightly bond the porous surface structure 333-1 and the pre-connected porous structure 333-2, thereby achieving a tight connection between the porous surface structure 333-1 and the substrate 333-3. The pre-connected porous structure 333-2 and the substrate 333-3 can be effectively bonded by various methods (including laser welding, resistance welding, etc.), for example... Figure 12b The resistance welding method described herein utilizes a non-porous base plate 333-4 as an intermediate in a pre-connected composite. In this example, the composite structure consisting of a porous surface structure and an intermediate connector is formed on the concave surface of the femoral condyle and covers the connection region of the femoral condyle. Specific details regarding the applicability of the femoral condyle to other embodiments are not elaborated here.

[0185] Similarly, the patellar prosthesis can also use the structure and method of any of the above embodiments or their variations to add a porous structure to its surface in contact with the bone.

[0186] The embodiments one to six of the present invention or their variations are not limited to the above-mentioned prosthesis examples, but can also be applied to such as spinal prostheses, ankle joints, shoulder joints, elbow joints, finger joints, toe joints, facet joints, temporomandibular joints, wrist joints, etc. The specific structures and principles are as described above, and the present invention will not elaborate further here.

[0187] Example 11:

[0188] The resistance welding methods mentioned in this invention include spot welding and / or projection welding. The following embodiments focus on illustrating the connection between the intermediate body and the substrate using projection welding resistance welding. In the resistance welding method of Embodiment 4 above, the pre-connected porous structure 192 has a certain porosity, the intermediate body 196 is located between the pre-connected porous structure 192 and the substrate 193, and the intermediate body 196 is a non-porous base plate 196. In fact, the intermediate body 196 can be the solid plate described in Embodiment 4, or the low-porosity porous structure described in Embodiment 11.

[0189] Therefore, the main difference from Embodiment 4 is that the pre-connected porous surface structure 41 (also called the first porous structure 41, whose function is equivalent to the pre-connected porous structure 192 in Embodiment 4) in Embodiment 11 includes a high-porosity region and a second porous structure 42 (as an intermediate) in a low-porosity region. The second porous structure 42 is located between the porous surface structure 41 and the substrate 23, such as... Figure 13a As shown.

[0190] For example, the porous surface structure 41 and the second porous structure 42 both contain numerous staggered supports (or beams), forming multi-directional, regularly shaped or irregularly shaped pores between these supports (or beams). The porosity of the porous surface structure 41 is denoted as a%, and the porosity of the second porous structure 42 is denoted as b%, where a% > b%. When b% equals 0, the second porous structure 42 is the intermediate of the solid structure described in Embodiment 1. Therefore, compared to the porous surface structure 41 constituting the porous surface structure, when the intermediate uses the second porous structure 42, the second porous structure 42 has a higher density, manifested as coarser supports (beams) and / or lower porosity in the second porous structure 42.

[0191] In this embodiment, both the porous surface structure 41 and the second porous structure 42 are made of conductive materials (such as metal materials). The porous surface structure 41 and the second porous structure 42 are integrally formed structures, for example, through 3D printing additive manufacturing processes or vapor deposition processes.

[0192] The porous surface structure 41 and the second porous structure 42 form a composite 4A, and the second porous structure 42 and the substrate 43 are effectively bonded by resistance welding, such as projection welding resistance welding: at least part of the support (or beam) at the bottom of the second porous structure 42 is in contact with the top of the substrate 43. Due to the contact resistance, resistance heat is generated, thereby heating the contact part of the two to a melting or plastic state, so that the second porous structure 42 and the top of the substrate 43 form a metal bond, so that the composite is connected to the substrate 43.

[0193] At least a portion of the top of the porous surface structure 41 is in contact with the positive electrode 44, and at least a portion of the bottom of the second porous structure 42 is in contact with the top of the substrate 43. The bottom of the substrate 43 is in contact with the negative electrode 45. The positive electrode 24 and the negative electrode 25 are made of metallic material. The top of the negative electrode 45 is in close contact with the bottom of the substrate 43, and the bottom of the positive electrode 44 is in close contact with the top of the porous surface structure 41.

[0194] The main difference between this embodiment and the resistance welding method in Embodiment 4 is that Embodiment 11 uses a second porous structure 42 in a low-porosity region to replace the solid intermediate body in Embodiment 4. Although the intermediate body in Embodiment 11 is a porous structure, its low porosity within a certain range ensures that the second porous structure 42 and the substrate 43 maintain a certain contact area, thereby ensuring a certain bonding efficiency. In principle, the smaller the porosity of the second porous structure 42, the higher the bonding efficiency between the composite 4A and the substrate 43, and vice versa. At the same time, the final bonding efficiency is also related to the specific arrangement of the staggered supports (or beams) inside the porous structure, which can be designed according to the actual application.

[0195] The lower surface of the aforementioned second porous structure 42 may also have protrusions 421, such as... Figure 13b As shown. When an electric current is applied, the current flows through the porous surface structure 41 and the second porous structure 42. The contact between the protrusion 421 of the second porous structure 42 and the top of the substrate 43 generates resistance heat, thereby forming a metal bond between the bottom of the second porous structure 42 and the top of the substrate 23. This results in the composite 4A formed by the porous surface structure 41 and the second porous structure 42 being tightly bonded to the substrate 43.

[0196] Example 12:

[0197] In the resistance welding method of Embodiment 4 described above, the top of the negative electrode 25 is in close contact with the bottom of the substrate 196, and the bottom of the positive electrode 24 is in close contact with the top of the pre-connected porous structure 192. Optionally, the positive electrode 24 and the negative electrode 25 are large planar electrodes, with the positive electrode 24 covering the top of the porous surface structure 21 and the negative electrode 25 covering the bottom of the substrate 193. Because the large planar positive electrode 24 of Embodiment 4 presses on the top of the pre-connected porous structure 192, the large planar positive electrode 24 contacts and compresses the surface of the porous surface structure 21, causing damage to the surface of the pre-connected porous structure 192. For example, it may cause indentation due to pressure, or blackening, indentation, and reduction of pore space due to heat generated by contact resistance.

[0198] To protect the pre-connected porous structure, the positive electrode 54 in this embodiment 12 is not a large planar electrode attached to the porous surface structure 51 (which functions similarly to the pre-connected porous structure 192 in embodiment 4). Instead, the positive electrode is divided into multiple positive electrode units 541, and the positive electrode units 541 are inserted vertically into the gaps 5a within the porous surface structure 51. Furthermore, the positive electrode units 541 are placed on top of the non-porous base plate 52 (as an intermediate body). Figure 14 As shown. Similarly, in this example, the porous surface structure 51 and the non-porous base plate 52 are integrally formed structures, for example, through 3D printing additive manufacturing processes or vapor deposition processes. The materials and manufacturing processes of the substrate 53, the non-porous base plate 52, and the porous surface structure 51 in this embodiment can be found in Embodiment 4, and will not be repeated here.

[0199] In this embodiment, each positive electrode unit 541 is connected in parallel and is connected to the positive terminal of the power supply, while the negative electrode 55 is connected to the negative terminal of the power supply. Multiple protrusions 521 are pre-fabricated on the bottom of the non-porous base plate 52. These protrusions 521 contact the top of the substrate 53, and the bottom of the substrate 53 contacts the negative electrode 55. Optionally, a gap 5a within the porous surface structure 51 serves as an insertion space for the corresponding positive electrode unit 541. This gap 5a is a pre-fabricated pore portion that extends from the surface of the porous surface structure 51, through the porous surface structure 51, and up to the top of the non-porous base plate 52, exposing the top of the non-porous base plate 52 within the gap 5a, allowing the bottom of the inserted positive electrode unit 541 to contact the top of the non-porous base plate 52.

[0200] In this embodiment, the positive electrode 54 does not come into contact with the surface of the porous surface structure 51, thus solving the problem of damage caused by resistive heat due to contact resistance between the surface of the porous surface structure and the positive electrode.

[0201] For example, the gap 5a is laterally fitted with the positive electrode monomer 541, such as a clearance fit. That is, the gap 5a needs to ensure that after the positive electrode monomer 541 is inserted, it is still separated from the adjacent porous surface structure to prevent the surface of the porous surface structure from being damaged by resistive heat, thereby protecting the surface of the porous surface structure. Optionally, the positive electrode monomer 541 is a columnar structure or other shapes. This embodiment is not limited to this, nor is it limited to other related examples.

[0202] For example, the positions of the multiple protrusions 521 on the bottom of the non-porous substrate 52 correspond to the positions of the various positive electrode units 541. For instance, the contact position between the positive electrode unit 541 and the top of the non-porous substrate 52 is located directly above each protrusion 521 or in the adjacent area of ​​the protrusion 521. This ensures that the current is smoothly conducted to the non-porous substrate 52 until it reaches the contact surface and adjacent area between the protrusion 521 and the top of the substrate 53, generating resistance heat to form a bond between the protrusion 521 and the top of the substrate 23. The shape of the protrusion 521 in this embodiment can be found in Embodiment 4, and will not be described in detail here.

[0203] It is worth noting that in this embodiment, the positive electrode is divided into multiple positive electrode units and inserted vertically into the gaps within the porous surface structure. This also applies to Embodiment Eleven, where the intermediate body is a second porous structure (with a lower porosity than the porous surface structure). Specifically, the positive electrode 44 in Embodiment Eleven is replaced with multiple positive electrode units, and each positive electrode unit is inserted vertically into the gaps within the porous surface structure 41. In this case, the pre-fabricated gap starts from the surface of the first porous structure, passes through the first porous structure, and extends to the second porous structure. Above the porous structure or inside the second porous structure, a portion of the second porous structure is exposed within the gap 5a, allowing the bottom of the inserted positive electrode unit to contact a portion of the second porous structure. Similarly, the gap is laterally fitted with the positive electrode unit, for example, a clearance fit. That is, the gap needs to ensure that after the positive electrode unit is inserted, it is still separated from the adjacent porous surface structure to prevent the surface of the porous surface structure from being damaged by resistive heat, thereby protecting the surface of the porous surface structure. Other specific structures and processes are the same as in this embodiment 12, and will not be described in detail here.

[0204] Example 13:

[0205] In the resistance welding method of the above embodiment four, the positive electrode 24 and the negative electrode 25 can be made of conductive material (e.g., metal material); the top of the negative electrode 25 is in close contact with the bottom of the substrate 193, and the bottom of the positive electrode 24 is in close contact with the top of the pre-connected porous structure 192; the positive electrode 24 and the negative electrode 25 are large planar electrodes, and the positive electrode 24 covers the top of the pre-connected porous structure 192, and the negative electrode 25 is attached to the bottom of the substrate 193.

[0206] The main difference from Embodiment 4 is that the positive electrode in Embodiment 13 is a flexible positive electrode 64, such as... Figure 15As shown. In this embodiment, the flexible positive electrode 64 is a large planar electrode and covers the top of the porous surface structure 61 (which functions as the pre-connected porous structure 192 in Embodiment 4). The negative electrode 65 is attached to the bottom of the substrate 63, and the non-porous base plate 62 is located between the porous surface structure 61 and the substrate 63. For example, the porous surface structure 61 and the non-porous base plate 62 are integrally formed structures, such as through 3D printing additive manufacturing processes or vapor deposition processes. The materials and manufacturing processes of the substrate 63, the non-porous base plate 62, and the porous surface structure 61 in this embodiment can be found in Embodiment 4, and will not be repeated here.

[0207] In this embodiment, since the flexible positive electrode 64 covers the top surface of the porous surface structure 61, it exerts a certain pressure on the surface of the porous surface structure 61. At this time, the flexible positive electrode 64 undergoes a certain flexible deformation under the interaction of pressure, which increases the contact area between it and the top of the porous surface structure 61 (compared to the contact area between the rigid positive electrode and the top of the porous surface structure under the same conditions). This not only reduces the contact resistance between the positive electrode 64 and the porous surface structure 61, improves or avoids surface damage caused by resistive heat on the porous surface (such as dents, blackening, reduction of pore space, etc.), and protects the surface of the porous surface structure, but also enhances current conduction, increases the welding bonding efficiency between the non-porous base plate 62 and the substrate 63, and increases the welding strength.

[0208] For example, the flexible material is a conductive material, such as copper foil or tin foil. This embodiment does not limit this, nor is it limited to other related examples. It can be designed according to the actual application.

[0209] As a variation of Example Thirteen, the following is an example: Figure 16aAs shown, a deformable good conductive medium 606 is added between the bottom of the positive electrode 604 and the top of the porous surface structure 601 (which functions as the pre-connected porous structure 192 in Embodiment 4), and the deformable good conductive medium 606 covers the top surface of the porous surface structure 601. Optionally, the deformable good conductive medium 606 is a continuous solid film, such as copper foil; or the deformable good conductive medium 606 is a good conductive wire or a mesh of good conductive material. Similarly, the intermediate body 602 is located between the porous surface structure 601 and the substrate 603, and the top of the negative electrode 605 is in close contact with the bottom of the substrate 603. The positive electrode 604 is a large planar electrode and covers the top surface of the easily deformable good conductive medium 606. Since the easily deformable good conductive medium 606 is very easy to deform, the contact area between it and the porous surface structure 601 is increased. This not only reduces the contact resistance between the porous surface structure 601 and the positive electrode 604 above it, reducing resistance heat and reducing surface damage to the porous surface structure 601, but also increases the current conduction effect, thereby increasing the welding strength between the intermediate 602 and the substrate 603.

[0210] Based on the above-described modifications, further extensions can be made as follows: The pores between the bottom of the positive electrode 6004 and the top of the porous surface structure 6001 (which functions equivalent to the pre-connected porous structure 192 in Example 4) are filled with a powder of a highly conductive material 6006 (or a highly conductive wire or mesh of a highly conductive material), such as... Figure 16b As shown, this reduces the contact resistance between the positive electrode 6004 and the surface of the porous surface structure 6001, thereby reducing surface damage to the porous surface structure 6001. Simultaneously, it increases current conduction and improves the welding efficiency between the intermediate 6002 and the substrate 6003. Preferably, the material of the highly conductive powder 6006 (or highly conductive wire) is the same as that of the porous surface structure 6001, for example, titanium powder (or titanium wire). Similarly, as... Figure 16b The intermediate 6002 is located between the porous surface structure 6001 and the substrate 6003, and the top of the negative electrode 6005 is in close contact with the bottom of the substrate 6003. In another different example, by spraying a conductive material onto the surface of the porous surface structure 6001, the contact resistance between the electrode and the porous surface structure can also be reduced, thereby reducing surface damage to the porous surface structure; however, this will not be elaborated upon in this invention.

[0211] Regardless of the aforementioned easily deformable conductive medium 606, conductive material powder 6006 (or conductive wire), sprayed conductive material, or liquid conductive agent, all of them need to be properly removed after the porous surface structure and the substrate are welded together to ensure that the pores of the porous surface structure remain open.

[0212] It is worth noting that after the porous surface structure is connected to the substrate in any of the above embodiments, a layer of hydroxyapatite (HA) coating can be separately sprayed onto the surface of the porous surface structure. The HA coating has good bioactivity and biocompatibility, which is beneficial to the subsequent bone ingrowth process. Alternatively, a coating containing antibacterial silver ions or other coatings containing cell growth factors can be separately sprayed onto the surface of the porous surface structure.

[0213] Based on the above, the present invention also provides a modified example, as follows:

[0214] To avoid or improve surface damage caused by resistance heat in porous surface structures, it is necessary to maximize the conductivity of the porous surface structure to reduce the contact resistance between it and the electrode. In this modified example, a molten material (a material with good conductivity) is infiltrated into the porous surface structure. The molten material almost completely fills the pores in the selected portion (the portion above the spacer layer) of the porous surface structure. At this point, it is necessary not only to limit the melting point of the molten material with good conductivity to a low value, but also to provide a spacer layer within the porous surface structure. The spacer layer is preferably made of a conductive material to prevent the molten material from penetrating downwards and flowing onto the intermediate body below, thus avoiding affecting the resistance welding effect. After the resistance welding process is completed, the bonded assembly is placed in a high-temperature environment. Since the melting point of the specific conductive medium is lower than that of the porous surface structure and the substrate (such as a titanium alloy), the high-temperature environment has little impact on the substrate. However, the low-melting-point conductive medium will melt, and this added low-melting-point conductive medium can be removed using existing technologies.

[0215] Example 14:

[0216] In Embodiment 11 above, the positive electrode 24 and negative electrode 25 are made of conductive material (metallic material). The top of the negative electrode 45 is in close contact with the bottom of the substrate 43, and the bottom of the positive electrode 44 is in close contact with the top of the first porous structure 41 in the high porosity region. The main difference from Embodiment 2 is that the positive electrode in Embodiment 14 is a flexible positive electrode 74 made of flexible material, not the metallic material in the above embodiments. Figure 17 As shown.

[0217] In this fourteenth embodiment, the flexible positive electrode 74 is a large planar electrode covering the top of the porous surface structure 71 (also called the first porous structure 71, which functions similarly to the pre-connected porous structure 192 in embodiment four) in the high-porosity region. The negative electrode 75 is attached to the bottom of the substrate 73. The second porous structure 72 in the low-porosity region is located between the first porous structure 71 and the substrate 73 in the high-porosity region. Optionally, the first porous structure 71 and the second porous structure 72 are integrally formed, for example, through 3D printing additive manufacturing or vapor deposition. The materials and manufacturing processes of the substrate 73, the second porous structure 72, and the first porous structure 71 in this embodiment can be found in embodiment two, and will not be repeated here.

[0218] In this embodiment, the flexible positive electrode 74 covers the top surface of the first porous structure 71, generating a certain pressure on the top surface of the first porous structure 71. At this time, the flexible material of the flexible positive electrode 74 will undergo a certain flexible deformation under the interaction of pressure, which increases the contact area between it and the top of the first porous structure 71 (compared to the contact area between the rigid positive electrode and the top of the first porous structure under the same conditions). This not only reduces the contact resistance between the positive electrode 74 and the porous surface structure 71, improves or avoids surface damage caused by resistive heat on the porous surface (such as depressions, blackening, reduction of pore space, etc.), and protects the surface of the porous surface structure, but also enhances current conduction, increases the welding bonding efficiency between the non-porous base plate 72 and the substrate 73, and increases the welding strength.

[0219] For example, the flexible material is a conductive material, such as copper foil or tin foil. This embodiment is not limited to this, nor is it limited to other related examples. It can be designed according to the actual application. Similar embodiment eleven ( Figure 13b As shown), the lower surface of the low-porosity base plate 72 may have protrusions to increase resistance welding efficiency.

[0220] Example 15:

[0221] Based on the resistance welding method in Embodiment 4 above, Embodiment 15 not only sets a non-porous base plate 812 (or a low-porosity porous structure) between the porous surface structure 811 (whose function is equivalent to the pre-connected porous structure 192 in Embodiment 4) and the substrate 813, but also pre-fabricates multiple protrusions on the bottom surface of the non-porous base plate 812, with the protrusions contacting the top of the substrate 813. Furthermore, it sets several support columns 816a on the surface of the non-porous base plate 812 near the porous surface structure. Figure 18aAs shown, the support column 816a is located between the non-porous base plate 812 and the positive electrode 814. The support column 816a is located inside the porous surface structure 811, and the top of the support column 816a is basically flush with the top of the porous surface structure 811. The height of the support column 816a is basically equal to the height of the porous surface structure 811. Similarly, the top of the negative electrode 815 in this embodiment is also in close contact with the bottom of the substrate 813. Of course, the height direction mentioned here is the orientation shown in the figure. The above orientation is only used for illustration and is not necessarily the orientation in actual application. The provisions of subsequent related embodiments are consistent with this.

[0222] In this embodiment, the support post 816a is a solid structure with good electrical conductivity. Each support post 816a is directly opposite to its corresponding protrusion below it, such that the area covered by the support post 816a at least partially overlaps with the contact portion between the protrusion and the substrate 813, and the size of the support post 816a matches the size of the protrusion.

[0223] Optionally, the non-porous base plate 812, the porous surface structure 811, and the support column 816a are integrally formed structures, for example, through 3D printing additive manufacturing processes or vapor deposition processes.

[0224] Although the surface of the porous surface structure 811 is still in partial contact with the positive electrode 814 above it in this example, since the support column 816a is a solid structure with good conductivity, and the porous surface structure 811 has pores, most of the current flowing out of the electrode preferentially passes through the solid structure with good conductivity, the support column 816a. This greatly reduces the surface damage of the porous surface structure 811 caused by resistance heat, and also enhances the current conduction effect. The welding bonding efficiency between the non-porous base plate 812 and the substrate 813 is increased, ensuring sufficient welding strength.

[0225] Example 16:

[0226] As a variation of Embodiment Fifteen, the variation of Embodiment Sixteen is as follows: In order to completely avoid damage to the surface of the porous surface structure caused by resistive heat generated by contact between the porous surface structure (the porous surface structure in this embodiment functions similarly to the pre-connected porous structure in Embodiment Four) and the positive electrode above it, such as... Figure 18b As shown, in this embodiment sixteen, the top of all the support columns 816b is set higher than the top surface of the porous surface structure, and the height of each support column 816b is higher than the height of the porous surface structure of its corresponding adjacent part. In this way, the positive electrode will contact the support column 816b at the higher position first, thereby avoiding the positive electrode from contacting the porous surface structure 811 at the lower position.

[0227] Since the height of the support column 816b in this example exceeds the porous surface structure, in order to ensure the basic function of the entire connection structure, the portion of the support column 816b that protrudes above the porous surface structure 811 can be removed after welding using processes such as cutting to ensure a smooth surface. Furthermore, as... Figure 18b As shown, the positive electrode can be not only Figure 18a The continuous large planar positive electrode shown can also be multiple segmented positive electrode units 814b, each segment of which is pressed on the top of the corresponding support post 816b, and the positive electrode units 814b are connected in parallel to a large planar electrode or directly to the positive terminal of the power supply.

[0228] Example 17:

[0229] Based on the above embodiments fifteen and sixteen, this embodiment seventeen is a further extension, and the idea behind this extension is as follows: Figure 18c As shown, the top of each support column 816c is lower than the top surface of the corresponding porous surface structure 811 (the porous surface structure 811 in this embodiment functions similarly to the pre-connected porous structure 192 in embodiment four). The height of the support column 816c is lower than the height of the porous surface structure. The support column 816a is hidden inside the porous surface structure 811, meaning that the porous structure is above the support column 816c. In this way, the positive electrode 814 will contact the surface of the porous surface structure 811 below it, causing the top surface of the porous surface structure 811 to sink slightly due to heat generated by contact resistance until it sinks to the top of the support column 816c (the maximum sinking can only reach the top of the support column; if the sinking is not significant, the sinking position is higher than the top of the support column). Because the support column 816c is a solid structure, it acts as a limiter, ensuring that the final height of the porous surface structure reaches the height of the support column, thus preventing the porous surface structure from being excessively compressed. Alternatively, the support column 816c may also have a recessed structure, so that the top of the support column 816c is lower than the top surface of the porous surface structure of the corresponding part, and the support column 816c can also play a limiting role.

[0230] For example, the non-porous base plate 812, the porous surface structure 811, and the support column 816c can be integrally formed structures, such as those achieved through 3D printing additive manufacturing processes or vapor deposition processes.

[0231] Although the top surface of the porous surface structure 811 is in contact with the positive electrode 814 above in this embodiment, the support column 816c is a solid structure with good conductivity. Because of the pores in the porous surface structure 811, most of the current selectively flows through the support column 816c until it reaches the protruding structure and the substrate 813. This ensures the welding strength between the non-porous base plate 812 and the substrate 813, and also reduces damage to the surface of the porous surface structure 811 to a certain extent. Although this embodiment still causes some damage to the surface of the porous surface structure, because the top of the support column 816c is always lower than the surface of the porous surface structure 811, it ultimately does not affect the basic function of the connection structure in the corresponding field.

[0232] based on Figure 18b and Figure 18c In another implementation example (not shown), a predetermined height position is selected on the support column that was originally higher than the surface of the porous surface structure 811, and the area above that position is designed as a porous structure, instead of... Figure 18b The diagram shows a support pillar with a flush surface. In this case, the positive electrode first contacts the top porous structure at a higher position. The top porous structure of the support pillar is pressed down and experiences slight sinking due to heat generated by contact resistance. The support pillar sinks to the aforementioned predetermined position, making it essentially flush with the adjacent porous structure (the maximum sinking is limited to the predetermined position; if the sinking is small, the sinking position is higher than the predetermined position). This design completely avoids surface damage caused by resistance heat generated from contact between the porous surface structure and the positive electrode above it, and eliminates the need for additional processing to remove the excess portion of the support pillar that protrudes above the porous surface structure.

[0233] Example 18:

[0234] In the above-described embodiment 15, a non-porous base plate 812 (or a low-porosity porous structure) is provided between the porous surface structure 811 and the substrate 813, and a plurality of protruding structures are pre-fabricated on the bottom surface of the non-porous base plate 812. The protruding structures are in contact with the top of the substrate 813. At the same time, a plurality of solid support columns 816a with good electrical conductivity are provided on the surface of the non-porous base plate 812 near the porous surface structure. The support columns 816a are located between the non-porous base plate 812 and the positive electrode 814.

[0235] The main difference from Embodiment Fifteen is that, in Embodiment Eighteen, the non-porous base plate 912a disposed between the porous surface structure 911 (whose function is equivalent to the pre-connected porous structure 192 in Embodiment Four) and the substrate 913 does not have the aforementioned protruding structure (such as bumps) on its bottom surface. Furthermore, multiple highly conductive support pillars 916a are disposed on the non-porous base plate 912a near the porous surface structure. The support pillars 916a are located between the non-porous base plate 912a and the positive electrode 914. Figure 19a As shown, the bottom surface of the non-porous base plate 912a is in almost planar contact with the substrate 813.

[0236] For example, the support post 916a is located inside the porous surface structure 911, and the height of the support post 916a is basically flush with the top surface of the porous surface structure. The height of the support post 916a is basically equal to the height of the porous surface structure. Similarly, the top of the negative electrode 915 is also in close contact with the bottom of the substrate 913.

[0237] For example, the non-porous base plate 812, the porous surface structure 811, and the support column 816a are integrally formed structures, such as those achieved through 3D printing additive manufacturing processes or vapor deposition processes.

[0238] In this embodiment eighteen, although the porous surface structure surface 911 still has partial contact with the positive electrode 814 above it, the support column 916a is a solid structure with good conductivity. Since there are pores in the porous surface structure 911, most of the current flowing out of the electrode preferentially passes through the solid structure support column 916a with good conductivity and then through the non-porous base plate 912a to the substrate 913. Even if the bottom end of the non-porous base plate 912a is not provided with a protruding structure, this embodiment eighteen has provided multiple columnar support columns 916a with good conductivity. There is still enough current and resistance heat to make the non-porous base plate 912a and the substrate 913 have sufficient welding strength, which can also reduce the damage to the surface of the porous surface structure to a certain extent.

[0239] Example 19:

[0240] As a variation of Embodiment Eighteen, the modified idea of ​​Embodiment Nineteen is as follows: Figure 19bAs shown, in this embodiment nineteen, in addition to the features of the non-porous base plate (or low-porosity porous structure) without protrusions described in embodiment eighteen, to completely avoid surface damage to the porous surface structure 911 due to heat generated by contact resistance, the tops of all support columns 916b are specifically set higher than the top surface of the porous surface structure, and the height of each support column 916b is higher than its corresponding adjacent portion of the porous surface structure. In this example, the positive electrode will contact the higher-positioned support column 916b first, thereby avoiding contact between the positive electrode and the lower-positioned porous surface structure 911. Furthermore, since the height of the support column 916b exceeds the porous surface structure, to ensure the basic function of the overall connection structure, after welding, the portion of the support column 916b exceeding the porous surface structure 911 can be removed by cutting or other processes to ensure a smooth surface. Further, as... Figure 19b As shown, the positive electrode can be not only Figure 19a The continuous large planar positive electrode shown can also be multiple segmented positive electrode units 914b, each segment of which is pressed on the upper end of the corresponding support post 916b, and the positive electrode units 914b are connected in parallel to a large planar electrode or directly to the positive terminal of the power supply.

[0241] Example 20:

[0242] Unlike the resistance welding method in Embodiment 4, the positive electrode 1014a in Embodiment 20 is not a large planar electrode attached to the porous surface structure 1011 (which functions similarly to the pre-connected porous structure 192 in Embodiment 4). Instead, the positive electrode 54 is divided into multiple positive electrode units 001, and the positive electrode units 001 are inserted vertically into the gaps 10a within the porous surface structure 1011. Figure 20a As shown, the positive electrode unit 001 is placed on top of the non-porous substrate 1012a (or a porous structure with low porosity). For example, multiple positive electrode units 001 are connected in parallel and are all connected to a large planar electrode or directly to the positive terminal of the power supply, while the negative electrode 1015 is connected to the negative terminal of the power supply.

[0243] Optionally, the porous surface structure 1011 and the non-porous base plate 1012a are integrally formed structures, for example, through 3D printing additive manufacturing process or vapor deposition process.

[0244] like Figure 20aAs shown, the voids 10a within the porous surface structure 1011 serve as the insertion space for the corresponding positive electrode unit 001, and the voids 10a are pre-fabricated pores. In this example, the bottom end of the positive electrode 1014a does not contact the top end of the porous surface structure 101 to avoid damage to the surface of the porous surface structure 1011 due to resistive heat. The voids 10a are laterally fitted with the positive electrode unit 001, for example, with a gap fit. That is, the voids 10a need to ensure that after the positive electrode unit 001 is inserted, it remains separated from the adjacent portion of the porous surface structure to prevent damage to that portion of the porous surface structure due to resistive heat.

[0245] The non-porous base plate in Embodiment 4 above is provided with raised structures (such as bumps) to generate greater contact resistance and resistive heat. However, Embodiment 20 is different. In this example, the bottom of the non-porous base plate 1012a is not provided with raised structures. However, since the positive electrode 1014a itself is in direct contact with the non-porous base plate 1012a, and each positive electrode unit 001 is connected to the power supply, the current flows directly from the positive electrode unit 001 and passes through the non-porous base plate 1012a and the substrate 1013 (without passing through the porous surface structure 1011). This still ensures sufficient current and resistive heat, so that the non-porous base plate 1012a and the substrate 1013 have sufficient welding strength.

[0246] Example 21:

[0247] As a variation of Embodiment 20, the variation of Embodiment 21 is that: several solid support structures 10b with good electrical conductivity are provided on the top surface of the non-porous base plate 1012b (or a porous structure with low porosity). The support structures 10b are placed in the pores reserved inside the porous surface structure 1011 (which functions similarly to the pre-connected porous structure 192 in Embodiment 4). Figure 20b As shown. The support structure 10b is used to place and support each positive electrode unit 001 in the positive electrode 1014a. The positive electrode unit 001 is located in the groove opened in the support structure 10b and cooperates with the groove to ensure good contact between all positive electrode units 001 and the corresponding support structure 10b.

[0248] For example, the non-porous base plate 1012b, the porous surface structure 1011, and the support column support structure 10b are integrally formed structures, such as those achieved through 3D printing additive manufacturing processes or vapor deposition processes.

[0249] Optionally, the top end of the support structure 10b is substantially flush with the top end of the porous surface structure 1011, and the height of the support structure 10b is substantially equal to the height of the porous surface structure 1011; or, the top end of the support structure 10b is lower than the top end of the porous surface structure 1011; or, the top end of the support structure 10b is higher than the top end of the porous surface structure 1011, and with the help of subsequent cutting processes, the top end of the final support structure 10b is flush with the top end of the porous surface structure 1011; the present invention does not limit the choice of which height design method to use. Similarly, in this example, even though the bottom of the non-porous base plate 1012b does not have a protruding structure, the positive electrode 1014a is electrically connected to the non-porous base plate 1012b through the solid support structure 10b with good conductivity. Moreover, each positive electrode unit 001 is connected to the power source, and the current flows directly from the positive electrode unit 001 and through the non-porous base plate 1012b and the substrate 1013 (without passing through the porous surface structure 1011). This ensures sufficient current and resistance heat, giving the non-porous base plate 1012b and the substrate 1013 sufficient welding strength.

[0250] Example 22:

[0251] Unlike Embodiment Seventeen, in Embodiment Twenty-Two, no non-porous base plate is provided between the porous surface structure 1111 and the substrate 1113. The improvement of Embodiment Twenty-Two is that at least a portion of the bottom of the porous surface structure 1111 (which corresponds to the pre-connected porous structure 192 in Embodiment Four) is connected to a solid, electrically conductive protruding structure 1112a (such as a protrusion). The protruding structure 1112a contacts the top of the substrate 1113. Figure 21a As shown, a solid, electrically conductive support column 1116a can be provided at any location within the porous surface structure 1111.

[0252] The support column 1116a and the protruding structure 1112a can be staggered, such as Figure 21a As shown. For example, the porous surface structure 1111, the protrusion structure 1112a, and the support column 1116a are integrally formed structures, for example, achieved through 3D printing additive manufacturing processes or vapor deposition processes.

[0253] Optionally, the support column 1116a is hidden inside the porous surface structure 1111, with the top end of the support column 1116a lower than the top end of the porous surface structure 1111 and the bottom end of the support column 1116a higher than the bottom end of the porous surface structure 1111.

[0254] In this example, the limiting effect of the support column 1116a can be used to prevent the porous surface structure 1111 from being over-compressed. This is because the positive electrode 1114 will first contact the top surface of the porous surface structure 1111 below it. Consequently, the surface of the porous surface structure 1111 will be damaged due to heat generated by contact resistance, resulting in a small amount of sinking until it sinks to the top of the support column 1116a (the maximum sinking can only reach the top position, and even if the sinking is not significant, the sinking position may be higher than the top position). Because the support column 1116a is a solid structure, it acts as a limiting element, ensuring the final porous surface structure... The height of the surface reaches the height of the support column; at the same time, the solid structure of the support column 1116a, which has good electrical conductivity, can be used to ensure that most of the current preferentially passes through the support column 1116a, and then through the porous surface structure near the support column 1116a before reaching the protruding structure 1112a. This can improve the damage problem caused by heat generated by contact resistance on the porous surface structure. Furthermore, in this example, the protrusions of the protruding structure 1112a are used to increase the contact resistance with the substrate 1113, so as to generate sufficient resistance heat and make the protruding structure 1112a and the substrate 1113 have sufficient welding strength.

[0255] Example 23:

[0256] The above embodiment twenty-two describes a staggered distribution of the support column 1116a and the protruding structure 1112a. As a variation of embodiment twenty-two, this embodiment twenty-three designs the protruding structure 1112b and the support column 1116b above it to be directly opposite each other, with at least partial overlap (e.g., partial overlap or complete overlap). Figure 21b As shown.

[0257] For example, the porous surface structure 1111 (which is equivalent to the pre-connected porous structure 192 in Example 4), the protrusion structure 1112b, and the support column 1116b are integrally formed structures, for example, by 3D printing additive manufacturing process or vapor deposition process.

[0258] In this twenty-third embodiment, the support column 1116b is hidden inside the porous surface structure 1111, the top of the support column 1116b is lower than the top of the porous surface structure 1111, and the height of the support column 1116b is lower than the height of the porous surface structure. The protruding structure 1112b is in contact with the top of the substrate 1113.

[0259] In this example, the support pillar 1116b can also be used to avoid excessive compression of the porous surface structure 1111. This is because the positive electrode 1114 will first contact the surface of the porous surface structure 1111 below it. Consequently, the surface of the porous surface structure 1111 will be damaged due to heat generated by contact resistance, causing a slight sinking until it sinks to the top of the support pillar 1116b (the maximum sinking can only reach the top position, and even then, the sinking position may be higher than the top position). Because the support pillar 1116b is a solid structure with good electrical conductivity, the support pillar... 1116b acts as a limit, ensuring that the final porous surface structure reaches the height of the support column. Simultaneously, the solid, highly conductive structure of the support column 1116a allows current to preferentially flow through it, mitigating damage to the top surface of the porous surface structure caused by heat generated from contact resistance. Furthermore, in this example, the protruding structure 1112b increases the contact resistance of the substrate 1113, generating sufficient resistive heat to ensure adequate welding strength between the protruding structure 1112b and the substrate 1113. It is worth noting that the welding efficiency of this embodiment 23 is better than that of embodiment 22 because the protruding structure 1112b and the support column 1116b are directly aligned, allowing current to flow directly through the protruding structure 1112b after passing through the support column 1116b. In embodiment 22, the current, after passing through the support column 1116a, must also pass through the pores in the porous surface structure before flowing through the protruding structure 1112a.

[0260] As a variation of this embodiment twenty-three, the idea behind this variation is as follows:

[0261] The height of the aforementioned support column being lower than the porous surface structure is modified as follows: the support column 1116c is located inside the porous surface structure 111, and the top of the support column 1116c is basically flush with the top of the porous surface structure. The height of the support column 1116c is basically equal to the height of the porous surface structure. In this case, the protruding structure 1112c also aligns with the support column 1116c above it, and the two at least partially overlap (e.g., partially overlap or completely overlap). Figure 21c As shown.

[0262] For example, the porous surface structure 1111, the protrusion structure 1112c, and the support column 1116c are integrally formed structures, for example, achieved through 3D printing additive manufacturing processes or vapor deposition processes. Other aspects of this modified embodiment can be found in Embodiments Fifteen and Twenty-Three above, and will not be repeated here.

[0263] Similarly, as another variation of this embodiment twenty-three, the idea behind this variation is:

[0264] The aforementioned provision that the height of the support columns is lower than that of the porous surface structure is modified by setting the top surface of all support columns 1116d to be higher than the top surface of the porous surface structure, such as... Figure 21d As shown, the height of each support column 1116d is higher than the height of the porous surface structure of its corresponding adjacent portion. At this time, the protruding structure 1112d also mates directly with the support column 1116d above it, with the two at least partially overlapping (e.g., partially overlapping or completely overlapping), as shown. Figure 21d As shown. For example, the porous surface structure 1111, the protrusion structure 1112d, and the support column 1116d are integrally formed structures, for example, achieved through 3D printing additive manufacturing processes or vapor deposition processes. Other aspects of this modified embodiment can be found in Embodiments Sixteen and Twenty-Three above, and will not be repeated here.

[0265] Example 24:

[0266] like Figure 22 As shown, in Embodiment 24, based on Embodiment 4, a plurality of limiting posts 1216 are further provided between the non-porous base plate 1212 (or a low-porosity porous structure) and the positive electrode 1214. The limiting posts 1216 are placed on the surface of the non-porous base plate 1212 near the porous surface structure 1211 (which corresponds to the pre-connected porous structure 192 in Embodiment 4). Optionally, the top surface of the limiting post 1216 is lower than the top surface of the corresponding portion of the porous surface structure, and the height of the limiting post 1216 is lower than the height of the porous surface structure. The limiting post 1216 is hidden inside the porous surface structure 1211. Similarly, in Embodiment 24, a plurality of protrusions 12a are pre-fabricated at the bottom end of the non-porous base plate 1212, and the protrusions 12a are in contact with the top of the substrate 1213.

[0267] In this embodiment twenty-four, the positive electrode 1214 first comes into contact with the surface of the porous surface structure 1211 at a higher position below it. Then, the surface of the porous surface structure 1211 is damaged due to heat generated by contact resistance and sinks until it sinks to the top position of the limiting post 1216 (the maximum sinking can only sink to the top position, and even when the sinking is not large, the sinking position is higher than the top position). Because the limiting post 1216 is a solid structure, the limiting post 1216 plays a limiting role, ensuring that the final height of the porous surface structure surface reaches the height position of the limiting post 1216, and avoiding excessive compression of the porous surface structure.

[0268] For example, the limiting post 1216 can be distributed directly opposite or staggered from the corresponding protrusions 12a below it. Furthermore, the material of the limiting post 1216 in this embodiment is not limited to whether it is a conductive or non-conductive material, as long as it ultimately satisfies the limiting function of the limiting post 1216 and prevents excessive compression of the porous surface structure. When the limiting post 1216 is a conductive material, the current preferably passes through the limiting post 1216, then through the porous surface structure near the limiting post 1216, and finally reaches the corresponding protrusion 12a. This can improve the damage problem caused by heat generated by contact resistance on the porous surface structure. When the limiting post 1216 is a non-conductive material, the current flows from the positive electrode 1214 to the porous surface structure 1211 and then to the protrusion 12a. Although the above-described situation in this embodiment still causes a certain degree of damage to the surface of the porous surface structure, since the limiting post 1216 is always lower than the surface of the porous surface structure 1212, it will ultimately not affect the basic function of the entire structure in the relevant field.

[0269] Example 25:

[0270] The porous surface structure of the present invention (the porous surface structure in this embodiment is equivalent to the pre-connected porous structure 192 in embodiment four) and the substrate are joined together by resistance welding (e.g., projection welding). When the area of ​​the workpiece to be welded is too large, a greater number of protrusions are required. Once the protrusions are determined, in order to ensure the welding strength between each protrusion and the substrate, the total current of the electrodes needs to be increased, which may lead to increased power supply equipment costs, electrode damage, and increased surface damage to the porous surface structure. In this case, the workpiece can be welded in sections and batches.

[0271] In this twenty-fifth embodiment, the porous surface structure 1311 is divided into regions and resistively welded to the substrate 1313 in batches, such as... Figure 23 As shown, a first positive electrode 1314-1 is connected above the porous surface structure 1311-1 corresponding to the first region, and a second positive electrode 1314-2 is connected above the porous surface structure 1311-2 corresponding to the second region. The top of the negative electrode 1315 is in close contact with the bottom of the substrate 1313. A non-porous base plate 1312 (or a low-porosity porous structure) is provided between the porous surface structure 1311 and the substrate 1313, and multiple protrusions are pre-fabricated on the bottom surface of the non-porous base plate 1312, with the protrusions contacting the top of the substrate 1313.

[0272] In this embodiment, the porous surface structure 1311 is subjected to resistance welding in sections. However, during the section welding, the positive electrode corresponding to each section may not be able to completely cover the corresponding porous surface structure. For example, the edge of any two adjacent sections that are divided may not be completely covered. In this case, the edge of each section may be slightly higher than the other covered parts (i.e., convex edge), which will affect the surface flatness of the porous surface structure 1311.

[0273] To overcome the aforementioned defects, the porous surface structure 1311 of this embodiment 25 is provided with grooves 13a, dividing the top of the porous surface structure 1311 into multiple regions, such as the porous surface structure 1311-1 in the first region and the porous surface structure 1311-2 in the second region shown in the figure. The groove 13a is elongated, with the porous surface structure 1311-1 in the first region and the porous surface structure 1311-2 in the second region located on opposite sides of the elongated groove 13a. The top of the groove 13a is lower than the top of the porous surface structure 1311. The height of the groove 13a is less than the height of the porous surface structure 1311.

[0274] For example, the main body of the non-porous base plate 1312, the groove 13a, and the porous surface structure 1311 are integrally formed structures, for example, through 3D printing additive manufacturing processes or vapor deposition processes. The groove 13a can also be formed by machining.

[0275] Figure 23 The diagram shows a gap between the first positive electrode 1314-1 and the second positive electrode 1314-2. In this case, the first positive electrode 1314-1 and the second positive electrode 1314-2 can be used sequentially. Figure 23 This is only a schematic representation of the location; or the first positive electrode 1314-1 and the second positive electrode 1314-2 can be pressed simultaneously onto the porous surface structure of the corresponding region without any order. Moreover, the coverage area of ​​the positive electrode corresponding to each region is greater than the surface area of ​​the porous surface structure 1311-1 of the corresponding region.

[0276] Since this embodiment is designed with a groove 13a, the side of the groove 13a that is close to the first positive electrode 1314-1 is referred to as the first side, and the other side of the groove 13a that is close to the second positive electrode 1314-2 is referred to as the second side.

[0277] In this embodiment, the porous surface structure 1311-1 in the first region is first connected to the substrate 1313 by resistance welding: the bottom surface of the first positive electrode 1314-1 covers the porous surface structure 1311-1 in the corresponding region, and the portion of the first positive electrode 1314-1 extending beyond the connection area does not exceed the edge of the second side of the groove 13a. Due to the heat generated by the contact resistance between the first positive electrode 1314-1 and the porous surface structure 1311-1 in the first region, the surface of the porous surface structure 1311-1 in the first region sinks slightly but does not form a convex edge; then the second... The porous surface structure 1311-2 of the region is resistance welded to the substrate 1313: the second positive electrode 1314-2 covers and contacts the surface of the porous surface structure 1311-2 of the corresponding region, and the portion of the second positive electrode 1314-2 extending beyond the connection region does not exceed the edge of the first positive electrode 1314-1 closest to the second positive electrode 1314-2. Due to heat generated by the contact resistance between the second positive electrode 1314-2 and the porous surface structure 1311-2 of the second region, the surface of the porous surface structure 1311-2 of the second region may slightly sink, but no convex edge will be formed. When the first positive electrode 1314-1 and the second positive electrode 1314-2 are connected sequentially, the first positive electrode 1314-1 and the second positive electrode 1314-2 can be the same electrode.

[0278] Alternatively, the first positive electrode 1314-1 and the second positive electrode 1314-2 can be pressed onto the porous surface structure of the corresponding region simultaneously without any order. In this case, the porous surface structure 1311-1 of the first region and the porous surface structure 1311-2 of the second region can simultaneously complete resistance welding with the substrate. The bottom surface of the first positive electrode 1314-1 covers the porous surface structure 1311-1 of the corresponding region, and the portion of the first positive electrode 1314-1 extending beyond the connection region does not exceed the edge of the second side of the groove 13a. The second positive electrode 1314-2 covers the surface of the porous surface structure 1311-2 of the corresponding region, and the portion of the second positive electrode 1314-2 extending beyond the connection region does not extend beyond the edge of the first side of the groove 13a.

[0279] This method solves the problem of protruding edges caused by segmented welding. The process requires controlling the position of the porous surface structure to be higher than the top of the groove 13a.

[0280] As a variation of this embodiment twenty-five, the following is provided:

[0281] like Figure 24As shown, a first positive electrode 1414-1 is connected above the porous surface structure 1411-1 corresponding to the first region, and a second positive electrode 1414-2 is connected above the porous surface structure 1411-2 corresponding to the second region. The top of the negative electrode 1415 is in close contact with the bottom of the substrate 1413. A non-porous base plate 1412 (or a low-porosity porous structure) is provided between the porous surface structure 1411 and the substrate 1413, and multiple protrusions are pre-fabricated on the bottom surface of the non-porous base plate 1412, which are in contact with the top of the substrate 1413.

[0282] The porous surface structure 1411 is provided with grooves 14a, dividing the top of the porous surface structure 1411 into multiple regions, such as the first region porous surface structure 1411-1 and the second region porous surface structure 1411-2 in the figure. The grooves 14a are elongated, with the first region porous surface structure 1411-1 and the second region porous surface structure 1411-2 located on opposite sides of the elongated groove 14a. The top of the groove 14a is lower than the top of the porous surface structure 1411. The height of the groove 14a is less than the height of the porous surface structure 1411. Since the grooves 14a are designed in this embodiment, the side of the groove 14a closer to the first positive electrode 1414-1 is designated as the first side, and the other side of the groove 14a closer to the second positive electrode 1414-2 is designated as the second side.

[0283] like Figure 24 As shown, there is an overlap between the first positive electrode 1414-1 and the second positive electrode 1414-2 (the first positive electrode 1414-1 and the second positive electrode 1414-2 are arranged in a specific order). Figure 24 (This is for illustrative purposes only).

[0284] The first positive electrode 1414-1 contacts the porous surface structure 1411-1 of the first region, and the first positive electrode 1414-1 extends beyond the groove 14a (i.e., the first positive electrode 1414-1 crosses the first side of the groove 14a but does not extend beyond the second side of the groove 14a), and further contacts a portion of the porous surface structure 1411-2 of the second region. After the welding process is completed, the surface of the porous surface structure 1411-2 of the second region has a small amount of sinking and the surface of the edge of the porous surface structure 1411-2 of the second region will have an indented protrusion. Then the second positive electrode 1414-2 contacts the porous surface structure 1411-2 of the second region, and the second positive electrode 1414-2 crosses the remaining part of the groove 14a or crosses the entire groove 14a. The second positive electrode 1414-2 extends beyond the indented protrusion, ensuring that the second positive electrode 1414-2 presses against the indented protrusion that may be generated by the porous surface structure 1411-2, so that the indented protrusion is flattened.

[0285] Alternatively, the first positive electrode 1414-1 contacts the porous surface structure 1411-1 in the first region, and the first positive electrode 1414-1 does not extend beyond the first side of the groove 14a. After the welding process is completed, the surface of the porous surface structure 1411-1 in the first region will have a slight sinking and an indentation protrusion. Then, the second positive electrode 1414-2 contacts the porous surface structure 1411-2 in the second region. The second positive electrode 1414-2 spans the entire groove 13a, and the second positive electrode 1414-2 extends beyond the indentation protrusion on the surface of the porous surface structure 1411-1, ensuring that the second positive electrode 1414-2 presses against the indentation protrusion on the surface of the porous surface structure 1411-1, so that the indentation protrusion is flattened. The process needs to control the sinking position of the porous surface structure to be higher than or basically flush with the top of the groove 14a.

[0286] Example 26:

[0287] Similar to Embodiment 25, Embodiment 26 also employs regional resistance welding. However, unlike Embodiment 25, to address the issue of indentation and protrusion caused by regional welding, the porous surface structure (not shown in the figure) of Embodiment 26 (equivalent to the pre-connected porous structure 192 in Embodiment 4) does not use a groove design. In this example, when adjacent regional porous surface structures are resist-welded sequentially, a protrusion appears at the edge of the first region after the first regional resistance welding because the coverage area of ​​the first positive electrode is smaller than the area of ​​the corresponding region (here, "protrusion" refers to a relative height relationship, meaning that the edge portion that has not been recessed is higher than other recessed portions). At this point, it is necessary to ensure that the second positive electrode, which is used for the next resistance welding, can cover the edge portion of the first region that previously protruded. In this way, the porous surface structure of the protruding edge portion will be recessed during the second resistance welding process, thereby avoiding the problem of edge indentation and protrusion caused by regional welding.

[0288] Example 27:

[0289] like Figure 25 As shown, in this embodiment 27, a limiting structure 15a is provided at the top of the non-porous base plate 1512. The limiting structure 15a is elongated and can be used as a reference for dividing areas. The limiting structure 15a is located at the edge of adjacent sides of any two adjacent areas. The top of the limiting structure 15a is lower than the top of the porous surface structure 1511, and the height of the limiting structure 15a is less than the height of the porous surface structure 1511. For example, the main body of the non-porous base plate 1512, the limiting structure 15a, and the porous surface structure 1511 are integrally formed structures, for example, through 3D printing additive manufacturing processes or vapor deposition processes.

[0290] The limiting structure 15a in this embodiment is a solid structure or a porous structure with a lower porosity than the porous surface structure 1311-1 and the porous surface structure 1311-2.

[0291] The positive electrode in this embodiment twenty-seven can be Figure 25 The image shows a large planar electrode 1514 with a porous surface structure covering multiple regions; it could also be... Figure 23 The first positive electrode 1314-1 and the second positive electrode 1314-2 with a gap exist in the middle, or Figure 24 The first positive electrode 1414-1 and the second positive electrode 1414-2 at least partially overlap. At this point, after the composite formed by the porous surface structure 1511 and the non-porous base plate 1512 is joined to the substrate 1513 by resistance welding, although the surface of the porous surface structure 1511 in each region experiences slight subsidence, no convex edges are formed, and the subsidence is limited by the limiting structure 15a. This method not only solves the problem of convex edges caused by regional welding but also limits the position of subsidence of the porous surface structure caused by the welding process.

[0292] Example 28:

[0293] It is worth noting that the present invention is not limited to the use of projection resistance welding alone in any of the above embodiments. It can also use spot resistance welding alone or combine projection resistance welding with spot resistance welding to bond the intermediate to the substrate. Specifically, spot resistance welding differs from projection resistance welding with raised structures. In spot resistance welding, the intermediate does not have raised structures. In one welding cycle, welding of one weld point is completed by a single electrode and each movement of the workpiece (e.g., a composite of a pre-connected porous structure and the intermediate and the substrate) or by a single electrode and each electrode movement, until a set number of weld points are completed, ensuring sufficient welding strength between the intermediate and the substrate. Furthermore, the present invention can also combine projection resistance welding and spot resistance welding. For example, after completing projection resistance welding in any of the above embodiments, spot resistance welding can be further performed to enhance the welding strength between the intermediate and the substrate.

[0294] The projection welding resistance welding method of this invention can weld multiple weld points simultaneously in one welding cycle, resulting in high production efficiency and no current shunting effect. Simultaneously, because the current density is concentrated at the projection point, the current density is high, allowing for welding with a smaller current and reliably forming a smaller weld nugget, overcoming the weld nugget offset phenomenon of spot welding resistance welding. The projection welding resistance welding method has accurate projection point positioning and consistent size, with relatively uniform strength at each point. Therefore, for a given welding strength, the size of a single projection welding weld point can be smaller than that of spot welding. Furthermore, due to the use of a large planar electrode and the projection point being located on the intermediate body, indentation on the exposed surface of the substrate can be minimized. At the same time, the large planar electrode has a low current density and good heat dissipation, resulting in much less electrode wear than spot welding, thus significantly reducing electrode maintenance and repair costs.

[0295] In the projection welding resistance welding process of any of the above embodiments, the raised structure, mainly the middle part, is subjected to greater pressure from the upper electrode and bonds with the substrate through resistance heat generated by contact. However, the side parts of the raised structure do not make sufficient contact with the substrate, resulting in failure to weld. To improve the welding strength between the raised structure of the intermediate body and the substrate, the intermediate body is welded multiple times and from multiple directions by rotating any one or more of the electrode, substrate, and intermediate body, ensuring that the raised structure is welded to the substrate from all directions.

[0296] Furthermore, as an extension of the above embodiments, the following is specifically included: Since the porous surface structure of some of the above embodiments (the porous surface structure in this embodiment is equivalent to the pre-connected porous structure in Embodiment 4) is in contact with the large planar positive electrode above it, the surface of the porous surface structure may be damaged (dented, blackened) due to heat generated by contact resistance. To overcome this defect and protect the surface of the porous surface structure, an insulating material is placed over the porous surface structure, and multiple holes are made in the insulating material at corresponding positions to accommodate the positive electrode or a highly conductive support pillar, etc., so that the porous surface structure below the insulating material at the un-holeed positions is not damaged. The thickness of the insulating material is appropriate, as it is necessary to ensure a complete current loop to allow the welding process to proceed sequentially.

[0297] Example 29:

[0298] like Figure 26 As shown, based on Embodiment 1 / Embodiment 2, the following improvements can be made: This Embodiment 29 uses the non-porous base plate from Embodiment 4 and Embodiment 11 ( Figure 5a or low porosity regions ( Figure 13bThe protrusions of the substrate 273 are removed and transformed into a non-porous or low-porosity intermediate plate structure 272 without protrusions. The substrate 273 is changed into a substrate composite consisting of a substrate body 273 and another protrusion structure 272A on its top surface. The structure 272A is pre-connected to the substrate body 273 (e.g., resistance welding / laser welding). The protrusions of 272A face the side of the non-protrusion intermediate plate structure 272, that is, the protrusions of the structure 272A are in contact with the bottom surface of the intermediate plate structure 272 in the composite.

[0299] A surface composite formed by a porous surface structure 271 (in this embodiment, the porous surface structure is equivalent to the pre-connected porous structure in Embodiment 4) and an intermediate plate structure 272, and a substrate composite formed by a protrusion structure 272A and a substrate body 273, are pressed between a positive electrode 274 and a negative electrode 275. When an electric current is applied, the current flows through the porous surface structure 271, the intermediate plate structure 272, and up to the protrusion of structure 272A. Due to the contact resistance, resistive heat is generated, which heats the protrusion of 272A and the bottom of the intermediate plate structure 272 to a melting or plastic state, ultimately achieving a solid connection between structures 272 and 272A, thereby tightly bonding the surface composite with the substrate composite. In another example, the surface composite still adopts the protruding structure 272 from Embodiments 4 and 11, with its protruding structure facing the substrate body 273. The protruding structure of structure 272 is staggered from the protruding structure of structure 272A above the substrate, ultimately achieving a tight bond between the surface composite and the substrate composite. The improvements described in Embodiment 29 are not limited to Embodiment 4 and can also be applied to any of the above embodiments (such as Embodiments 11 to 28), which will not be elaborated upon here.

[0300] Example 30:

[0301] like Figure 28 As shown, this embodiment 30 is based on the above embodiment 4 with the following improvements:

[0302] In this embodiment, a first pre-connected porous structure 192 and a second pre-connected porous structure 192' are respectively provided on the upper and lower sides of the substrate 193. First, the first pre-connected porous structure 192 is effectively combined with the upper side of the substrate 193 and the second pre-connected porous structure 192' is effectively combined with the lower side of the substrate 193 by various methods (including laser welding, resistance welding, etc.).

[0303] When resistance welding is used to combine the first pre-connected porous structure 192 with the upper side of the substrate 193 or the second pre-connected porous structure 192' with the lower side of the substrate 193, each pre-connected porous structure can be directly contacted with the corresponding side of the substrate for resistance welding. Alternatively, resistance welding can be used to combine each pre-connected porous structure with the corresponding side of the substrate through its respective intermediate. For example, the first pre-connected porous structure 192 can be effectively combined with the upper side of the substrate 193 in advance through the first intermediate 196, and the second pre-connected porous structure 192' can be effectively combined with the lower side of the substrate 193 in advance through the second intermediate 196'.

[0304] In a specific example, such as Figure 28 As shown, both the first pre-connected porous structure 192 and the second pre-connected porous structure 192' are porous structures containing numerous staggered supports (or beams), forming multi-directional, regularly or irregularly shaped pores between these supports (or beams). The first intermediate body 196 is located between the first pre-connected porous structure 192 and the upper side of the base 193, and the second intermediate body 196' is located between the second pre-connected porous structure 192' and the lower side of the base 193. Optionally, the first intermediate body 196 and / or the second intermediate body 196' are non-porous base plates, i.e., solid base plates, such as... Figure 28 As shown. The first pre-connected porous structure 192, the second pre-connected porous structure 192', the first intermediate 196, and the second intermediate 196' are all made of conductive materials (such as metal materials). The first pre-connected porous structure 192 and the first intermediate 196 are integrally formed structures, as are the second pre-connected porous structure 192' and the second intermediate 196', which can be achieved, for example, through 3D printing additive manufacturing processes or vapor deposition processes. For example, the substrate 193 is solid, which is beneficial to the overall strength of the connected structure. The substrate 193 can be made of conductive materials (such as metal materials), formed by various methods such as forging and casting, and can be subjected to various machining processes.

[0305] like Figure 28 As shown, the first pre-connected porous structure 192 and the first intermediate body 196 are pre-connected to form a first pre-connected composite, and the first intermediate body 196 is effectively bonded to the upper side of the substrate 193 by resistance welding, so that the first pre-connected composite is connected to the upper side of the substrate 193. Similarly, the second pre-connected porous structure 192' and the second intermediate body 196' are pre-connected to form a second pre-connected composite, and the second intermediate body 196' is effectively bonded to the lower side of the substrate 193 by resistance welding, so that the second pre-connected composite is connected to the lower side of the substrate 193.

[0306] In this embodiment, each pre-connected porous structure is connected to the two sides of the substrate by projection welding resistance welding, forming a connection interface. Then, a certain gap is left between the first pre-connected porous structure 192 and the porous surface structure 191 above it (for bone ingrowth), and a certain gap is left between the second pre-connected porous structure 192' and the porous surface structure 191' below it (for bone ingrowth). High-temperature molten polymer material is injected into each gap and simultaneously penetrates into the porous surface structure and the pre-connected porous structure, or polymer material is placed in the gap and then heated and melted to simultaneously penetrate into the porous structure of the porous surface structure and the pre-connected porous structure. Finally, the first polymer material intermediate layer 194 and the second polymer material intermediate layer 194' are formed on both sides. At this time, the first polymer material intermediate layer 194 is simultaneously and tightly bonded to both the first porous surface structure 191 and the first pre-connected porous structure 1922, and the second polymer material intermediate layer 194' is simultaneously and tightly bonded to both the second porous surface structure 191' and the second pre-connected porous structure 192', thereby achieving a tight bond between the porous surface structure and the substrate, such as... Figure 28 As shown.

[0307] like Figure 27 As shown, the resistance welding method used in this embodiment 30 is implemented as follows: First, similar to the resistance welding method in embodiment 4, this embodiment provides a first pre-connected composite material formed by pre-connecting a first porous surface structure 281-1 (any porous surface structure in this embodiment is equivalent to the pre-connected porous structure 192 in embodiment 4) and a first non-porous base plate 282-1 on one side of the top of the substrate 283. The first pre-connected composite material is placed between the positive electrode 284 and the top surface of the substrate 283, and at least a portion of the top of the first porous surface structure 281-1 is in contact with the positive electrode 284. A plurality of first protrusion structures are pre-fabricated on the bottom of the first non-porous base plate 282-1, and the first protrusion structures are in contact with the top of the substrate 283. Simultaneously, a second pre-connected composite is provided on one side of the bottom of the substrate 283, formed by pre-connecting a second porous surface structure 281-2 and a second non-porous base plate 282-2. The second pre-connected composite is placed between the bottom surface of the substrate 283 and the negative electrode 285, and at least a portion of the bottom of the second porous surface structure 281-2 is in contact with the negative electrode 285. The second pre-connected composite has the same structure as the first pre-connected composite and is axially symmetrical about the substrate 283. Following the principle of Embodiment 4, the first and second pre-connected composites are simultaneously resistance-welded to the upper and lower surfaces of the substrate 283, respectively, to achieve a pre-connected connection between the first and second pre-connected composites and the substrate. This variation is also applicable to any of the above embodiments, and will not be elaborated further in this invention.

[0308] Example 31:

[0309] In the above embodiment four, the pre-connected porous structure 192 and the substrate 193 are effectively bonded in advance by resistance welding as an example. However, the present invention is not limited to the above resistance welding method. Laser welding can also be used to achieve a firm connection between the pre-connected porous structure 192 and the substrate 193. The laser welding method can be referred to in embodiment thirty-one and its variant examples for the bonding method of porous surface structure and substrate. In this case, the pre-connected porous structure 192 is equivalent to the porous surface structure in embodiment thirty-one and its variant examples.

[0310] like Figure 29 As shown, in this embodiment 31, the porous surface structure 10 (equivalent to the pre-connected porous structure 192 in embodiment 4) and the intermediate 20 (equivalent to the intermediate 196 in embodiment 4) are formed into a composite. The composite is connected to the substrate 30 through the connection between the intermediate 20 and the substrate 30 (equivalent to the substrate 193 in embodiment 4).

[0311] The preferred substrate 30 is solid, which is beneficial to the overall strength of the connection structure. The example substrate 30 is made of metallic material, formed by various methods such as forging, casting, and powder metallurgy, and can be subjected to various machining processes. The intermediate body 20 and the substrate 30 are preferably effectively bonded together by laser welding. Figure 29 The symbol 40 in the figure represents the welding point 40 between the two, and the location of the welding point 40 can be freely chosen according to the application requirements. In some examples, it is not limited to certain parts between the intermediate body 20 and the base 30, which can be joined by bonding, using connectors (screws, etc.), or other various connection methods, which will not be elaborated in this article.

[0312] The intermediate body 20 can be solid or a porous structure. The porous structure comprises numerous staggered supports (or beams) that form multi-directional, regularly shaped or irregularly shaped pores. When the intermediate body 20 is constructed using a second porous structure compared to the first porous structure constituting the porous surface structure 10, the second porous structure has a higher density, manifested as coarser supports (beams) and / or lower porosity.

[0313] In a preferred example, both the porous surface structure 10 and the intermediate 20 are made of metallic materials. The porous surface structure 10 and the intermediate 20 are integrally formed structures, for example, through 3D printing additive manufacturing processes, vapor deposition processes, or sintering.

[0314] This invention does not specifically limit the welding position; at least one pair of contact surfaces can be selected for welding according to application needs. Figure 29The intermediate body 20 shown includes a bottom and is generally in the form of a sheet or plate; the bottom of the intermediate body 20 is welded to the top surface of the substrate 30. Alternatively, in some examples, the intermediate body 20 includes a bottom and extends to at least one side above the bottom to form the periphery of the intermediate body 20; the bottom and periphery of the intermediate body 20 may have the same or different shapes, dimensions (such as thickness), densities, etc.

[0315] Figure 30 The illustration shows a case where a recess is provided on the substrate 30. A composite of the porous surface structure 10 and the intermediate body 20 is embedded within the recess, with the bottom 21 and periphery 22 of the intermediate body 20 correspondingly contacting the top surface 31 and side edge 32 of the recess in the substrate 30, and these contact surfaces are welded and fixed. Of course, the present invention does not limit the shape, size, or position of the recess on the substrate 30; nor is it limited to other examples where welding and fixing are performed only between the intermediate body 20 and a portion of the contact surfaces of the substrate 30 or its recess (while not welding between other contact surfaces); for example, welding may be performed only between the bottom 21 of the intermediate body 20 and the top surface 31 of the recess in the substrate 30, or only between the periphery 22 of the intermediate body 20 and the side edge 32 of the recess. Furthermore, in some examples, the composite may have both a portion embedded in the recess and a portion contacting a non-recessed location on the substrate 30 (such as a portion contacting the surface 33 of the substrate 30 next to the recess opening). These contact portions of the composite may be welded to corresponding locations on the substrate 30, or only some of them may be welded to corresponding locations on the substrate 30.

[0316] exist Figure 30 Based on the example, the following structural changes can be made: Figure 30 The side 32 of the recessed portion of the intermediate base 30 is approximately perpendicular to the top surface 31 of the recess; the periphery 22 of the intermediate body 20 is also approximately perpendicular to the bottom 21. Figure 31 All sides of the recessed portion of the central base 30 (shown as both sides in the diagram) are inclined slopes 321; Figure 32 Part of the side of the recessed portion of the central base 30 is a slope 321 (one side of the recess is a slope, and the other side is approximately perpendicular to the top surface of the recess). Figure 31 or Figure 32 In the figure, the inclined side of the recessed part of the base 30 indicates that there is a set angle between the side of the recessed part of the base 30 and the top surface of the recess; the angle is preferably an acute angle; then the recess (section) is a trapezoid that is narrow at the top and wide at the bottom, and the further away from the top surface of the recess, the smaller the opening of the recess.

[0317] Therefore, the periphery of the intermediate body 20 is also correspondingly provided as an inclined slope 221, which also has a set angle (preferably an acute angle) with the bottom of the intermediate body 20; thus, when the composite of the porous surface structure 10 and the intermediate body 20 is embedded in the recess, the inclined periphery (sloping surface 221) of the intermediate body 20 can cooperate with the inclined side (sloping surface 321) of the recess of the base 30; the bottom and periphery of the intermediate body 20 are in corresponding contact with the top surface and side of the recess of the base 30, and are welded and fixed on these contact surfaces respectively. The present invention does not specifically limit the location, welding position, shape (such as changing to curved surface, arc surface, etc.), size, etc. of the contact surface between the intermediate body 20 and the base 30 (or its recess), and can be designed according to the actual application.

[0318] exist Figure 30 Based on the example, the following structural changes can also be made: Figure 33 or Figure 34 In the example, a snap-fit ​​structure is provided between the recess of the base 30 and the contact surface of the intermediate body 20. Figure 33 Each side of the recessed portion of the base 30 and each periphery of the intermediate body 20 (shown as both sides) are provided with a corresponding snap-fit ​​structure; Figure 7 The diagram shows that a portion of the recessed area of ​​the base 30 and a portion of the periphery of the intermediate body 20 are provided with snap-fit ​​structures (one side of the diagram has a snap-fit ​​structure, while the other side does not). The snap-fit ​​structure, for example, is a limiting opening 322 on the side of the recessed area, such as a recessed hole or groove; correspondingly, a protrusion 222, such as a pin or strip, is provided on the periphery of the intermediate body 20, which can be inserted into the limiting opening 322 at the corresponding position. When the composite of the porous surface structure 10 and the intermediate body 20 is embedded in the recessed area, the intermediate body 20 and the recessed area of ​​the base 30 are positioned by the snap-fit ​​structure, and the bottom and periphery of the intermediate body 20 are in corresponding contact with the top surface and side of the recessed area of ​​the base 30, and are welded and fixed at these contact surfaces respectively.

[0319] Figure 33 or Figure 34 The protrusion 222 in the shown snap-fit ​​structure extends laterally outward from the bottom of the intermediate body 20, and is basically located at the junction of the periphery and bottom of the intermediate body 20 (the corresponding position of the limiting opening 322 on the base 30). In other examples, the protrusion in the snap-fit ​​structure can be formed at other positions on the periphery and / or bottom of the intermediate body 20 (the corresponding position of the limiting opening on the base 30), not limited to the junction of the periphery and bottom. Alternatively, without affecting the embedding of the composite, the protrusion in the snap-fit ​​structure can also be formed on the top surface and / or side of the base 30 (the corresponding position of the limiting opening on the intermediate body 20). Therefore, the present invention does not specifically limit the components, positions, shapes, and sizes of the snap-fit ​​structure, and can be designed according to actual application conditions.

[0320] The beveled and snap-fit ​​structures at the contact points between the recessed portion of the base 30 and the intermediate body 20 in the above examples can be provided individually or in combination. These structures are collectively referred to as positioning structures, primarily to ensure that the base 30 (equivalent to base 193 in Embodiment 4) and the intermediate body 20 (equivalent to intermediate body 196 in Embodiment 4) can be tightly attached together without displacement during welding; and they can also play an auxiliary fixing role after welding is completed. The beveled or limiting port and other positioning structures at the contact surface of the base 30 can be formed together with the base 30 body during the molding process, or they can be formed by machining after the base 30 body is formed. The beveled or protruding positioning structures at the contact surface of the intermediate body 20 are preferably integrally formed with other parts of the intermediate body 20, using 3D printing or other processes (but not limited to forming the beveled or protruding structures by certain machining methods after the intermediate body 20 body is formed in some examples).

[0321] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above description. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A method for connecting a porous surface structure and a substrate, characterized in that, a gap is left between the porous structure at the substrate and the side of the porous surface structure close to the substrate; a molten thermoplastic material is arranged in the gap; the molten thermoplastic material in the gap penetrates into the interior of the porous surface structure and the porous structure at the substrate, respectively; the thermoplastic material after solidification connects the porous surface structure and the porous structure at the substrate, and connects the porous surface structure to the substrate; wherein the thermoplastic material is a high polymer material, and the elastic modulus of the thermoplastic material is less than the elastic modulus of the substrate; the porous structure at the substrate comprises a pre-connected porous structure: the substrate is made of a solid structure or a porous structure, and has at least one connection area pre-connected with a pre-connected composite; the pre-connected porous structure is pre-connected or integrally formed with an intermediate body to form a pre-connected composite; the thermoplastic material penetrates into the interior of the pre-connected porous structure on one side of the substrate, and the pre-connected porous structure is connected with the porous surface structure by the thermoplastic material; the intermediate body comprises an intermediate plate structure and / or a plurality of protruding structures, and the intermediate body is located on the side of the pre-connected composite close to the substrate; the pre-connected porous structure is connected and fixed with the substrate through the intermediate body.

2. The method according to claim 1, characterized in that, the molten thermoplastic material is injected into the gap, or the thermoplastic material is placed in the gap and then heated to melt to form the molten thermoplastic material; when the intermediate body comprises an intermediate plate structure and a plurality of protruding structures, the protruding structures are arranged on the side of the intermediate plate structure close to the substrate, and the protruding structures are in contact with and connected to the substrate through the protruding points; when the intermediate body comprises a plurality of protruding structures arranged dispersedly, the protruding structures are formed on the side of the pre-connected porous structure close to the substrate, and the protruding structures are in contact with and connected to the substrate through the protruding points.

3. The method according to claim 1, characterized in that, a spacing layer is arranged on the side of the porous surface structure close to the substrate, and the spacing layer is another porous structure with a higher density than the porous surface structure; the molten thermoplastic material penetrates into the interior of the porous structure where the spacing layer is arranged and the porous structure at the substrate, respectively; the spacing layer is used to prevent the thermoplastic material from penetrating into the porous surface structure; or, a spacing layer is arranged in the interior of the porous surface structure, and the spacing layer is a solid structure; the molten thermoplastic material penetrates into the pore part between the spacing layer and the porous structure at the substrate, respectively; the spacing layer is used to prevent the thermoplastic material from penetrating into the part of the porous surface structure away from the substrate; wherein the porous surface structure and the spacing layer are integrally formed.

4. The method according to claim 1, characterized in that, the substrate and the intermediate body in the pre-connected composite are fixedly connected by laser welding or resistance welding. In the resistance welding, the pre-bonded composite on one side of the substrate and the substrate are placed between the first polarity electrode and the second polarity electrode and current is passed through to perform resistance welding; or the pre-bonded composite on one side of the substrate, the substrate and the pre-bonded composite on the other side of the substrate are placed between the first polarity electrode and the second polarity electrode and current is passed through to perform resistance welding. The intermediate body is a solid structure, or the intermediate body is a second porous structure with a porosity lower than that of the pre-bonded porous structure. The substrate, the pre-bonded porous structure and the intermediate body are made of conductive material.

5. The method of claim 4, wherein, Any one of a1-a8 is included: The contact surface of the first polarity electrode and the pre-bonded porous structure is a plane or a curved surface; The first polarity electrode is a flexible electrode which matches the surface of the pre-bonded porous structure by flexible deformation under pressure; The first polarity electrode is divided into a plurality of electrode monomers; the plurality of electrode monomers are connected in parallel to another plane electrode and the other plane electrode is connected to the power supply end; or the plurality of electrode monomers are connected in parallel and directly connected to the power supply end; The first polarity electrode is divided into a plurality of electrode monomers; the electrode monomers are inserted into the pre-prepared gap in the pre-bonded porous structure; the inserted electrode monomers are in conductive contact with the intermediate body, or pass through the pre-bonded porous structure to be in conductive contact with the intermediate body; The first polarity electrode is divided into a plurality of electrode monomers; the electrode monomers pass through the surface of the pre-bonded porous structure until they penetrate the surface of the intermediate body or the interior of the intermediate body, so that the inserted electrode monomers are in conductive contact with the intermediate body; wherein the inserted electrode monomers and the pre-bonded porous structure are in lateral gap cooperation, and the electrode monomers and the pre-bonded porous structure are not in contact; When the first polarity electrode is divided into a plurality of electrode monomers, a conductive support column is arranged in the pre-prepared gap of the pre-bonded porous structure, and the support column is provided with a groove for placing the electrode monomers, and the inserted electrode monomers are in conductive contact with the support column; The first polarity electrode is in conductive contact with the pre-bonded porous structure and / or the intermediate body; the first polarity electrode is in contact with the insulating support column arranged in the pre-bonded porous structure and is limited; all or at least part of each support column is located in the pre-bonded porous structure; The pre-bonded porous structure is provided with a conductive support column; all or at least part of each support column is located in the pre-bonded porous structure; the support column is in conductive contact with any one or more of the following components: the first polarity electrode, the pre-bonded porous structure and the intermediate body.

6. The method of claim 4, wherein, Any one of b1-b6 is included: The pores in at least part of the pre-bonded porous structure are filled with conductive material; The pores in at least part of the pre-bonded porous structure are filled with powder-like or wire-like or net-like conductive material; At least part of the surface of the pre-bonded porous structure is laid with a solid thin film-like or wire-like or net-like deformable conductive medium, and the deformable conductive medium is located between the first polarity electrode and the pre-bonded porous structure; At least part of the surface of the pre-bonded porous structure and the first polarity electrode are sprayed with a solid conductive medium or a liquid conductive agent; b5 injecting a molten conductive medium into at least part of the pores of the pre-connected porous structure; the melting point of the conductive medium is lower than the melting point of the substrate and / or the melting point of the pre-connected porous structure; b6 providing a conductive medium in at least part of the pores of the pre-connected porous structure, and making the conductive medium molten by high temperature; the melting point of the conductive medium is lower than the melting point of the substrate and / or the melting point of the pre-connected porous structure.

7. The method of claim 2, wherein the connection region is provided according to any one of c1-c7: c1 the substrate comprises a connection region, which is in contact with and connected to an intermediate of a pre-connected composite; c2 the substrate comprises a connection region, which is in contact with and connected to an intermediate of a pre-connected composite, respectively; c3 the substrate comprises a plurality of connection regions, which are in contact with and connected to an intermediate of a pre-connected composite; c4 the substrate comprises a plurality of connection regions, each of which is in contact with and connected to an intermediate of a pre-connected composite; c5 the substrate comprises a plurality of connection regions, each of which is in contact with and connected to an intermediate of a pre-connected composite, respectively; c6 the substrate comprises a plurality of connection regions, which are in the same plane, or a part of the connection regions are not in the same plane as other connection regions on the substrate; c7 the substrate comprises a plurality of connection regions, each of which is independently arranged, or at least a part of the connection regions on the substrate are in communication with other connection regions on the substrate.

8. A prosthesis, wherein the prosthesis is provided with a connection structure comprising a porous surface structure and a substrate; the substrate is used to form a prosthesis body; at least part of the surface of the prosthesis body is a connection region; the connection structure is prepared by the method of claim 1-7 for connecting the porous surface structure and the substrate; wherein the porous surface structure is on the surface of the connection region of the prosthesis body.

9. The prosthesis of claim 8, wherein the substrate is pre-connected with a surface connection layer, so that the surface connection layer is between the intermediate of the pre-connected composite and the substrate body; the surface connection layer comprises a plurality of protruding structures, the protruding points of the protruding structures are in contact with and connected to the intermediate of the pre-connected composite; wherein the side of the intermediate close to the substrate is planar; or the protruding structures provided on the side of the intermediate close to the substrate are staggered with the protruding structures of the surface connection layer.

10. The prosthesis of claim 8, wherein the pre-connected porous structure comprises a plurality of support columns, all or at least part of each support column is located in the pre-connected porous structure; the support column is a conductor or an insulator; the surface of the support column away from the substrate is above, flush with, or below the surface of the pre-connected porous structure, the support column is a solid structure or a porous structure.

11. The prosthesis of claim 10, wherein the intermediate comprises an intermediate plate structure and a plurality of protruding structures, or comprises a plurality of dispersedly arranged protruding structures, the support column is arranged and in contact with the protruding structures contained in the intermediate. ​ ​ ​ ​ ​ Alternatively, the intermediate body comprises an intermediate plate structure and a plurality of protruding structures, or comprises a plurality of protruding structures arranged dispersedly, the support column is distributed in dislocation with the protruding structures comprised by the intermediate body and does not contact with the protruding structures.

12. The prosthesis of claim 8, wherein, The intermediate body and the base are provided with positioning structures at the at least one pair of contact surfaces therebetween, and further comprise any one of e1-e5: The positioning structure comprises a limiting opening and a protrusion insertable therein, which are respectively formed on two surfaces of the pair of contact surfaces where the positioning structure is located; The pair of contact surfaces where the positioning structure is located form the positioning structure through the surface shapes and sizes matched with each other; The base is provided with a recess; the pre-connected composite body comprises an embedded part embedded in the recess, and there is at least one pair of contact surfaces between the embedded part and the recess of the base, and the positioning structure is formed through the surfaces matched with each other; The base is provided with a recess; the pre-connected composite body comprises an embedded part embedded in the recess, and there is at least one pair of contact surfaces between the embedded part and the recess of the base, and the positioning structure is formed through the surfaces matched with each other; The base is provided with a recess; the pre-connected composite body comprises an embedded part embedded in the recess, and there is at least one pair of contact surfaces between the embedded part and the recess of the base, and the positioning structure is formed through the surfaces matched with each other; 13. The prosthesis of any one of claims 8-12, wherein, The prosthesis is any one of the following: femoral stem, acetabular cup, tibial tray, femoral condyle, patella, spinal cage, spinal intervertebral facet joint, ankle joint, shoulder joint, elbow joint, finger joint, toe joint, artificial intervertebral disc, mandibular joint, wrist joint.

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