Titanium alloy artificial bone joint with low friction coefficient and preparation method thereof

Abstract

The application discloses a titanium alloy artificial bone joint with low friction coefficient, which comprises joint parts and a gasket structure arranged at the connecting position of adjacent joint parts, wherein the joint part comprises an action part and a connecting part; the action part is matched and combined with the gasket structure; and the connecting part is fixedly connected with natural bone or artificial bone; the action part and the connecting part both comprise a base structure arranged at the inner side; the action part further comprises an intermediate layer attached to the outer side of the base structure and a surface layer attached to the outer side of the intermediate layer; and the connecting part further comprises a fusion layer attached to the outer side of the base structure. The titanium alloy artificial bone joint with low friction coefficient is prepared by the preparation method, so that the mechanical property, biocompatibility and low friction coefficient of the titanium alloy artificial bone joint can be remarkably improved, the defects in the prior art are overcome, and a more high-quality solution is provided for the clinical application of the artificial bone joint.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of bone joints, in particular to a titanium alloy artificial bone joint with low friction coefficient and a preparation method thereof. BACKGROUND

[0002] The research and application of artificial bone joints is one of the important directions in the field of modern medicine, especially in orthopedic surgery, the application of artificial joints greatly improves the quality of life of patients. Titanium alloy has become an important material for preparing artificial bone joints due to its good mechanical properties, biocompatibility and corrosion resistance. However, the existing titanium alloy artificial bone joint still has some significant defects in mechanical properties, biocompatibility and low friction coefficient.

[0003] Titanium alloy has high strength and low density, which makes it one of the ideal materials for artificial bone joints. However, the existing titanium alloy artificial bone joint often has fatigue damage and wear problems during long-term use. Since the human joint bears repeated stress and strain in daily activities, it requires artificial joint materials to have excellent tensile strength and yield strength. The existing titanium alloy artificial bone joint is not ideal in this respect, and long-term use may lead to a decrease in the mechanical properties of the material, affecting the service life and function of the joint.

[0004] Biocompatibility is one of the important indicators for evaluating the quality of artificial bone joint materials. Although the existing titanium alloy artificial bone joint shows good biocompatibility as a whole after being implanted in the human body, there are still some problems. For example, some titanium alloy materials may cause local inflammatory reactions, leading to tissue rejection of the implant. In addition, the existing titanium alloy surface treatment technology is limited, and it is difficult to achieve good combination with the surrounding bone tissue, affecting bone healing and long-term stability of the joint. The problem of cytotoxicity also limits the wide application of the existing titanium alloy artificial bone joint to some extent.

[0005] The normal operation of the joint depends on the low friction and high lubricity between the joint surfaces. The existing titanium alloy artificial bone joint still does not perform well in this respect. The surface friction coefficient of titanium alloy is relatively high, which means that friction and wear will be intensified during joint movement, thereby affecting the function and durability of the joint. High friction coefficient not only causes discomfort to patients during use, but also may cause wear and inflammation of the tissues around the joint, further reducing the service life of the artificial joint.

[0006] In summary, the existing titanium alloy artificial bone joint has a lot of room for improvement in terms of mechanical properties, biocompatibility and low friction coefficient. These defects limit the wide application and promotion of artificial bone joints in clinical practice. In view of these problems, it is particularly important to develop a titanium alloy artificial bone joint with higher mechanical properties, better biocompatibility and lower friction coefficient. SUMMARY

[0007] In view of the above-mentioned deficiencies in the prior art, the present application aims to provide a titanium alloy artificial bone joint with low friction coefficient and a preparation method thereof, which significantly improves the mechanical properties, biocompatibility and low friction coefficient of the titanium alloy artificial bone joint, overcomes the deficiencies in the prior art, and provides a more superior solution for the clinical application of artificial bone joints.

[0008] The technical solution adopted by the present application to achieve the above-mentioned purpose is as follows: a titanium alloy artificial bone joint with low friction coefficient, comprising joint pieces and a gasket structure arranged at the connection between adjacent joint pieces, wherein the joint pieces comprise an action part and a connecting part, the action part is combined with the gasket structure, and the connecting part is fixedly connected with a natural bone or an artificial bone.

[0009] The action part and the connecting part each comprise a base structure arranged on the inner side, the action part further comprises an intermediate layer attached to the outer side of the base structure and a surface layer attached to the outer side of the intermediate layer, and the connecting part further comprises a fusion layer attached to the outer side of the base structure.

[0010] In some embodiments, in order to ensure that the base structure in the action part and the connecting part has excellent mechanical properties, the following technical solution is provided.

[0011] The base structure comprises the following raw material components in proportion by weight fraction:

[0012] Titanium: ≥ 85%,

[0013] Nitrogen: 5-10%,

[0014] Aluminum: 2-8%,

[0015] Vanadium: 1-2%.

[0016] In some embodiments, in order to further improve the structural strength, biocompatibility, processing performance and corrosion resistance of the base structure, the following technical solution is provided.

[0017] The base structure further comprises the following raw material components in proportion by weight fraction:

[0018] Iron: ≤ 0.25%,

[0019] Zirconium: ≤ 0.3%,

[0020] Molybdenum: ≤ 1.5%.

[0021] In some embodiments, to ensure that the fusion layer can be stably attached to the base structure of the connecting part to form a unified whole, ensure that the fusion layer has good biocompatibility and can effectively fuse with the natural bone, and improve the stability of the artificial bone joint and the natural bone, the following technical solutions are provided.

[0022] The fusion layer comprises the following raw material components in a proportion by weight fraction:

[0023] Titanium: 85-90%,

[0024] Bioactive glass: 10-15%;

[0025] The bioactive glass comprises the following raw material components in a proportion by weight fraction:

[0026] Silicon dioxide: 45-52%,

[0027] Calcium oxide: 25-30%,

[0028] Sodium oxide: 10-15%,

[0029] Phosphorus oxide: 2-6%.

[0030] In some embodiments, to ensure that the intermediate layer can be stably attached to the base structure of the working part to form a unified whole, while further improving the strength and rigidity of the entire working part, enhancing its impact resistance and fatigue resistance, ensuring long-term stable use, and playing a role in load bearing and stress dispersion, the following technical solutions are provided.

[0031] The intermediate layer is uniformly provided with anchor holes on the side facing the pad structure, and comprises the following raw material components in a proportion by weight fraction:

[0032] Titanium: 85-95%,

[0033] Tantalum: 5-10%,

[0034] Niobium: 1-5%,

[0035] Ceramic matrix composite: ≤5%;

[0036] The ceramic matrix composite comprises the following raw material components in a proportion by weight fraction:

[0037] Aluminum oxide: 70-80%,

[0038] Zirconium oxide: 20-30%,

[0039] Additive: ≤5%;

[0040] The additive comprises one or more of silicon dioxide, titanium oxide, and rare earth oxides.

[0041] In some implementations, to ensure that the surface layer can be stably attached and formed into a unified whole on the outer surface of the intermediate layer, and at the same time ensure that the surface layer has a very low friction coefficient and cooperates smoothly with the pad structure, the following technical solutions are provided.

[0042] The surface layer adopts a nitrogen-containing high-carbon nanocrystalline titanium alloy coating, which comprises the following raw material components in percentage by weight:

[0043] Nanocrystalline titanium: ≥80%,

[0044] Nitrogen: 4-8%,

[0045] Carbon: 2-5%.

[0046] In some implementations, to reduce the friction between the pad structure and the surface layer of the action surface, the following technical solutions are provided.

[0047] The pad structure comprises the following raw material components in percentage by weight:

[0048] Polyether ether ketone: 90-95%,

[0049] Tetrafluoroethylene fiber: 5-10%.

[0050] A method for preparing a low-friction titanium alloy artificial bone joint, for preparing the low-friction titanium alloy artificial bone joint described above, comprising the following steps for preparing the joint member:

[0051] S1-1, preparation of the base structure:

[0052] S1-1-1: A blank is prepared by using a melting casting method;

[0053] S1-1-2: The surface of the blank is sequentially subjected to cutting finishing, corner position polishing treatment, sand blasting treatment, and cleaning to obtain a base structure presenting a connecting portion and an action portion;

[0054] S1-2, preparation of the fusion layer:

[0055] S1-2-1: The base structure of the action portion is subjected to cladding treatment, an outer cladding shell is installed on the outside of the action portion, and a fusion layer is made on the outer surface of the base structure of the connecting portion by using a gas phase deposition method;

[0056] S1-2-2: The cladding shell on the outside of the action portion is removed, and the base structure of the action portion is cleaned;

[0057] S1-3, preparation of the intermediate layer:

[0058] S1-3-1: The fusion layer of the connecting part is coated, an outer coating shell is installed outside the fusion layer, and an intermediate layer is made on the outer surface of the base structure of the action part by a vapor deposition method;

[0059] S1-3-2: A hole is drilled on the side of the intermediate layer facing the pad structure, the anchor hole is processed, and a surface layer is made on the outer surface of the intermediate layer by a spraying process, so that the surface layer enters the anchor hole to enhance the bonding stability of the surface layer and the intermediate layer.

[0060] S1-3-3: The outer coating shell of the fusion layer is removed, and the joint part is washed as a whole to complete the preparation of the joint part;

[0061] It also includes the following preparation steps of the pad structure:

[0062] S2: An integrally formed pad structure is processed by a melting pouring method.

[0063] In some embodiments, in order to ensure that the action part base structure and the fusion layer of the connecting part are coated, the vapor deposition operation of the exposed part is stably carried out, and the following technical solutions are provided.

[0064] The coating shell is made of high-temperature resistant material, and the coating process and the step of removing the coating shell include:

[0065] S3-1: The coating shell is assembled on the outer side of the base structure of the action part or the outer side of the fusion layer of the connecting part in a detachable manner;

[0066] S3-2: The coating shell on the outer side of the base structure of the action part or the outer side of the fusion layer of the connecting part is removed.

[0067] The beneficial effects of the present application are:

[0068] 1. The application prepares a titanium alloy blank by a melting casting method, and performs fine processing such as cutting, polishing and sand blasting treatment, so that the base structure has higher smoothness and geometric precision, and lays a solid foundation for the attachment of the fusion layer and the intermediate layer. The preparation of the fusion layer and the intermediate layer adopts a vapor deposition method, which not only enhances the structural strength of the material, but also significantly improves the tensile strength and yield strength. Experimental results show that the tensile strength of the titanium alloy artificial bone joint provided by the application reaches 950 MPa, and the yield strength reaches 920 MPa, which are significantly better than the existing 850 MPa and 800 MPa. The improvement of the overall mechanical properties ensures the stability and durability of the joint in long-term use.

[0069] 2. In terms of biocompatibility, the present application significantly reduces cytotoxicity by preparing a low-toxicity fusion layer and an intermediate layer on the surface of the titanium alloy, and the cell proliferation rate reaches 95%. The surface treatment process of the present application makes the titanium alloy material more closely combined with the surrounding bone tissue, reduces the risk of inflammatory reaction and tissue rejection. Through cell culture experiment verification, the titanium alloy artificial bone joint provided by the present application shows obvious advantages in biocompatibility, which is beneficial to the healing of bone tissue and the long-term stability of artificial joint.

[0070] 3. The present application uses a spraying process to prepare a nitrogen-containing high-carbon nanocrystalline coating on the surface of the titanium alloy, and drills anchor holes in the intermediate layer, so that the surface layer material enters the anchor holes, enhancing the bonding stability between the surface layer and the intermediate layer. After the friction and wear test, the friction coefficient of the titanium alloy artificial bone joint provided by the present application is only 0.20, which is significantly lower than 0.35 of the existing titanium alloy artificial bone joint. The realization of low friction coefficient not only reduces the wear and energy consumption in joint movement, but also improves the comfort of patients and the service life of the joint.

[0071] In summary, the present application significantly improves the mechanical properties, biocompatibility and low friction coefficient of the titanium alloy artificial bone joint by innovative preparation method and surface treatment process, overcomes the shortcomings in the prior art, and provides a more superior solution for the clinical application of artificial bone joint. BRIEF DESCRIPTION OF DRAWINGS

[0072] Figure 1 is a structure schematic diagram of the titanium alloy bone joint in the cut state in the present application;

[0073] Figure 2 is a structure schematic diagram of the intermediate layer and the surface layer in the disassembled state.

[0074] In the figure: 1 joint part, 101 action part, 102 connecting part, 11 base structure, 12 intermediate layer, 121 anchor hole, 13 surface layer, 14 fusion layer, 2 gasket structure. DETAILED DESCRIPTION

[0075] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0076] Please refer to Figures 1-2 The technical solutions of the titanium alloy artificial bone joint with low friction coefficient and the preparation method thereof provided by the present application will be described in detail in terms of action mechanism in combination with the following embodiments. Example 1

[0077] The low-friction coefficient titanium alloy artificial bone joint comprises joint parts 1 and a pad structure 2 arranged at the connecting position of adjacent joint parts 1, and the joint part 1 comprises an action part 101 and a connecting part 102.

[0078] The action part 101 and the connecting part 102 both comprise a base structure 11 arranged at the inner side, the action part 101 further comprises an intermediate layer 12 attached to the outer side of the base structure 11 and a surface layer 13 attached to the outer side of the intermediate layer 12, and the connecting part 102 further comprises a fusion layer 14 attached to the outer side of the base structure 11.

[0079] The low-friction coefficient titanium alloy artificial bone joint provided by the application has reasonable design, and the cooperation between various structures involved is strong, so that the functions of the respective structures can be fully exerted.

[0080] The joint part 1 comprises the action part 101 and the connecting part 102, and the functions are distinct, the action part 101 cooperates with the pad structure 2 to provide a low-friction surface required by joint movement, and the connecting part 102 is fixedly connected with the natural bone or the artificial bone to provide stable support for the joint.

[0081] In the structural design of the action part 101, the base structure 11 provides structural support and bears the main load, has good mechanical properties, and ensures the stability of the structure itself during joint movement; the intermediate layer 12 can further improve the strength and rigidity of the entire action part 101, enhance the impact resistance and fatigue resistance of the action part 101, ensure long-term stable use, and play the roles of bearing and dispersing stress, so that the base structure 11, the surface layer 13 and the intermediate layer 12 can be stably attached together to form an integral structure, avoiding problems such as delamination and cracking, and prolonging the service life of the joint; the surface layer 13 has extremely low friction coefficient and excellent wear resistance, and directly acts with the pad structure 2 to achieve the effect of joint movement.

[0082] In the structural design of the connecting part 102, the base structure 11 thereof is the same as the base structure 11 in the action part 101, and has good compatibility with the human bone tissue, so that the connecting part 102 can be stably connected with the natural bone; the fusion layer 14 can further increase the good fusion with the natural bone or the artificial bone, ensure firm connection, and avoid loosening.

[0083] The pad structure 2 is arranged at the connecting position of adjacent joint parts 1, buffers the impact force generated during joint movement, reduces stress concentration, protects the joint and the surrounding tissue, and cooperates with the action part 101 to further optimize the low-friction characteristics of the joint.

[0084] The design of each structure focuses on the key targets of reducing friction, dispersing stress, improving stability, etc. Through mutual cooperation, long-term stability and reliable operation of the artificial joint can be achieved. Embodiment 2

[0085] In order to ensure that the base structure 11 in the action part 101 and the connecting part 102 has excellent mechanical properties, the following technical solutions are provided.

[0086] The base structure 11 includes the following raw material components in weight fraction:

[0087] Titanium: ≥85%,

[0088] Nitrogen: 5-10%,

[0089] Aluminum: 2-8%,

[0090] Vanadium: 1-2%.

[0091] In the titanium alloy composition used in the base structure 11, titanium is the main component, which has good biocompatibility and mechanical properties. Nitrides can improve the hardness and wear resistance of the metal, and also improve the compatibility with human tissues. Aluminum can improve the strength and hardness of titanium alloy to ensure its mechanical properties. Vanadium can improve the corrosion resistance of titanium alloy in addition to improving its strength.

[0092] In order to further improve the structural strength, biocompatibility, processing performance and corrosion resistance of the base structure 11, the following technical solutions are provided.

[0093] The base structure 11 also includes the following raw material components in weight fraction:

[0094] Iron: ≤0.25%,

[0095] Zirconium: ≤0.3%,

[0096] Molybdenum: ≤1.5%.

[0097] Iron can be selectively added to improve the strength of titanium alloy and improve its heat treatment performance. Zirconium can also be selectively added to improve the processing performance and biocompatibility of titanium alloy. Molybdenum is selectively added to improve the corrosion resistance and strength of titanium alloy. Embodiment 3

[0098] In order to ensure that the fusion layer 14 can be stably attached and integrated on the base structure 11 of the connecting part 102 to form a unified whole, ensure that the fusion layer 14 has good biocompatibility and can effectively fuse with natural bone, and improve the stability of the artificial bone joint and natural bone, the following technical solutions are provided.

[0099] The fusion layer 14 includes the following raw material components in the following proportions by weight fraction:

[0100] Titanium: 85-90%,

[0101] Bioactive glass: 10-15%;

[0102] The bioactive glass includes the following raw material components in the following proportions by weight fraction:

[0103] Silicon dioxide: 45-52%,

[0104] Calcium oxide: 25-30%,

[0105] Sodium oxide: 10-15%,

[0106] Phosphorus oxide: 2-6%.

[0107] Silicon dioxide is the network former of the bioactive glass, which gives the bioactive glass good mechanical strength and chemical stability. In vivo, silicon dioxide can be hydrolyzed to release Si ions, stimulate the surrounding cells to produce silicate and phosphate precipitates, and promote the formation of new bone tissue.

[0108] Calcium oxide can improve the bioactivity and dissolution rate of the bioactive glass. The release of calcium ions is conducive to cell adhesion and proliferation, and can also combine with phosphate ions to form hydroxyapatite and form chemical bonds with natural bone.

[0109] Sodium oxide can adjust the dissolution rate of the glass to maintain appropriate bioactivity reaction kinetics in vivo. The release of sodium ions helps the mineralization of extracellular matrix and the formation of new bone.

[0110] Phosphorus oxide can further enhance the bioactivity of the bioactive glass and promote the formation of hydroxyapatite. At the same time, the release of phosphate ions is conducive to cell differentiation and bone mineralization.

[0111] The components in the bioactive glass will undergo a series of complex chemical-biological reactions in vivo, which together play a role in promoting bone tissue regeneration and fusion. With the addition of titanium, the fusion layer 14 can be stably attached and integrated to the outer surface of the base structure 11, forming a unified whole. Example 4

[0112] In order to enable the intermediate layer 12 to be stably attached and integrated to the base structure 11 of the action part 101, form a unified whole, and further improve the strength and stiffness of the entire action part 101, enhance its impact resistance and fatigue resistance, ensure long-term stable use, and play a role in bearing and dispersing stress, the following technical solutions are provided.

[0113] The intermediate layer 12 is uniformly provided with anchor holes 121 on the side facing the liner structure 2, and the intermediate layer 12 comprises the following raw material components in proportion by weight fraction:

[0114] Titanium: 85-95%,

[0115] Tantalum: 5-10%,

[0116] Niobium: 1-5%,

[0117] Ceramic matrix composite: ≤5%;

[0118] The ceramic matrix composite comprises the following raw material components in proportion by weight fraction:

[0119] Alumina: 70-80%,

[0120] Zirconia: 20-30%,

[0121] Additives: ≤5%;

[0122] The additives include one or more of silicon dioxide, titanium oxide, and rare earth oxides.

[0123] Titanium, as the main component, has excellent properties such as high strength, light weight, and corrosion resistance. Tantalum is a high-density, corrosion-resistant, and biocompatible metal element. Adding tantalum to titanium alloy can improve the strength, hardness, and wear resistance of the alloy. Niobium is a metal element with good biocompatibility, which can improve the mechanical properties of the alloy. Adding an appropriate amount of niobium to the titanium alloy can increase the strength, toughness, and fatigue resistance of the alloy, and also helps to improve the corrosion resistance of the alloy, ensuring the long-term stability of the joint prosthesis in a physiological environment.

[0124] Alumina is a high-strength, high-hardness ceramic material that can significantly improve the mechanical strength and stiffness of the composite material. It has excellent wear resistance and corrosion resistance, which can significantly enhance the durability of the composite material, and has good thermal stability at high temperatures, which is beneficial to improving the fatigue resistance of the composite material.

[0125] Zirconia has high fracture toughness, which can effectively inhibit the propagation of cracks and improve the impact resistance of the composite material. It expands in volume during the phase transition, which can generate compressive stress to prevent crack propagation and enhance wear resistance. When the anchor holes 121 are opened on the side of the intermediate layer 12 facing the liner structure 2, it can effectively avoid cracking around the anchor holes 121. The chemical stability of zirconia also helps to improve the durability of the composite material in a biological environment.

[0126] As for the additives, silicon dioxide can improve the density and strength of the ceramic, titanium oxide can improve the thermal shock resistance and wear resistance of the ceramic, and rare earth oxides (such as yttrium oxide) can improve the fracture toughness and creep resistance of the ceramic.

[0127] The anchor hole 121 can improve the effective adhesion of the surface layer 13 to the outer surface of the intermediate layer 12, improve the adhesion effect of the two, ensure that the intermediate layer 12 and the surface layer 13 can be stably adhered together to form a whole structure, and avoid problems such as delamination and cracking.

[0128] To ensure that the surface layer 13 can be stably adhered to the outer surface of the intermediate layer 12 and form a unified whole, and at the same time ensure that the surface layer 13 has a very low friction coefficient and cooperates with the pad structure 2 to run smoothly, the following technical solutions are provided.

[0129] The surface layer 13 adopts a nitrogen-containing high-carbon nanocrystalline titanium alloy coating, which includes the following raw material components in percentage by weight:

[0130] Nanocrystalline titanium: ≥80%,

[0131] Nitrogen: 4-8%,

[0132] Carbon: 2-5%.

[0133] The nanoscale grain size of nanocrystalline titanium can significantly improve the hardness and strength of the titanium alloy, thereby enhancing the wear resistance of the surface layer 13, and the nanocrystalline structure can also improve the thermal stability and chemical stability of the material, which is beneficial to improve the durability of the surface layer 13.

[0134] The nitrogen element can form a TiN phase in the nanocrystalline titanium matrix, further improving the hardness and wear resistance of the surface layer 13, and the presence of the TiN phase can also improve the lubricity of the surface layer 13, reducing the friction coefficient with the corresponding pad structure 2.

[0135] The carbon element can form a TiC phase in the nanocrystalline titanium, further enhancing the strength and toughness of the surface layer 13, and the presence of the TiC phase can also improve the chemical stability of the surface layer 13, improving the corrosion resistance and wear resistance.

[0136] Other trace elements can also be added on this basis, specifically a small amount of Al, V, Fe and other elements, to further optimize the performance of the surface layer 13, such as improving corrosion resistance and oxidation resistance.

[0137] During the combination of the surface layer 13 and the intermediate layer 12, part of the surface layer 13 material can penetrate into the anchor hole 121 of the intermediate layer 12 to form a stable anchoring structure to strengthen the stability and unity of the combination of the two. Example 5

[0138] To reduce the friction force of the pad structure 2 and the surface layer 13 of the action part 101, the following technical solutions are provided.

[0139] The gasket structure 2 comprises the following raw material components in weight fraction:

[0140] Polyether ether ketone: 90-95%,

[0141] Tetrafluoroethylene fiber: 5-10%.

[0142] Polyether ether ketone (PEEK) is a high-performance engineering plastic with excellent mechanical strength, rigidity and high-temperature resistance. Its good chemical resistance and biocompatibility can ensure the stability and safety of the gasket structure 2 in a biological environment, and its low friction coefficient and excellent self-lubricating property are conducive to achieving low-friction motion with the surface layer 13.

[0143] Tetrafluoroethylene (PTFE) fiber has extremely low friction coefficient and excellent wear resistance, which can further reduce the friction coefficient with the surface layer 13. In addition, the addition of PTFE fiber can also enhance the crack resistance of the PEEK matrix and improve the overall reliability and durability. The synergistic effect between PTFE fiber and PEEK matrix can achieve more stable low-friction properties.

[0144] The PEEK matrix provides excellent mechanical strength and rigidity, capable of withstanding high loads during joint movement. Example 6

[0145] A method for preparing a low-friction titanium alloy artificial bone joint, for preparing the low-friction titanium alloy artificial bone joint described above, comprising the following steps for preparing the joint piece 1:

[0146] S1-1, preparation of the base structure 11:

[0147] S1-1-1: A blank is prepared by using the method of melting casting;

[0148] S1-1-2: The surface of the blank is sequentially subjected to cutting finishing, corner polishing treatment, sandblasting treatment and cleaning to obtain the base structure 11 exhibiting the connecting part 102 and the acting part 101;

[0149] S1-2, preparation of the fusion layer 14:

[0150] S1-2-1: The base structure 11 of the acting part 101 is subjected to cladding treatment, and a cladding shell is installed outside the acting part 101. The fusion layer 14 is made on the outer surface of the base structure 11 of the connecting part 102 by using the method of vapor deposition;

[0151] S1-2-2: The cladding shell outside the acting part 101 is removed, and the base structure 11 of the acting part 101 is cleaned;

[0152] S1-3, preparation of the intermediate layer 12:

[0153] S1-3-1: The fusion layer 14 of the connecting part 102 is coated, an outer coating shell is installed outside the fusion layer 14, and an intermediate layer 12 is made on the outer surface of the base structure 11 of the action part 101 by vapor deposition;

[0154] S1-3-2: Drill holes on the side of the intermediate layer 12 facing the gasket structure 2 to process anchor holes 121, and use a spray process to make a surface layer 13 on the outer surface of the intermediate layer 12, so that the surface layer 13 enters the anchor holes 121 to enhance the stability of the surface layer 13 and the intermediate layer 12.

[0155] S1-3-3: Remove the outer coating shell of the fusion layer 14, and clean the entire joint part 1 to complete the preparation of the joint part 1;

[0156] It also includes the following preparation steps for the gasket structure 2:

[0157] S2: Use a melt pouring method to process an integrally formed gasket structure 2.

[0158] A titanium alloy blank is prepared by a melt casting method, laying a foundation for subsequent processing. The blank is subjected to cutting and finishing to process the structure of the action part 101 and the connecting part 102 thereon. The corner parts are then polished to remove impurities and burrs thereon. Finally, the entire structure is sprayed to roughen the surface, facilitating the stable adhesion of the fusion layer 14 and the intermediate layer 12 thereon and forming a unified whole.

[0159] When generating the melt layer, the action part 101 is first coated by a coating process to avoid the melt layer material falling on the action part 101 affecting the structural stability of the action part 101. The fusion layer 14 is prepared on the base surface of the connecting part 102 by vapor deposition. Then, the outer coating shell of the action part 101 is removed, and the remaining coating shell on the base surface is cleaned.

[0160] When generating the intermediate layer 12, the fusion layer 14 is first coated by a coating process to avoid the materials of the intermediate layer 12 and the surface layer 13 falling on the fusion layer 14 affecting the normal functioning of its design function. The intermediate layer 12 is prepared by vapor deposition to improve the overall structural strength. Anchor holes 121 are drilled on the intermediate layer 12 to improve the bonding effect of the intermediate layer 12 and the surface layer 13. The surface layer 13 is prepared by a spray process to enter the anchor holes 121 to enhance the bonding. Finally, the outer coating shell of the connecting part 102 is removed, and the entire joint part 1 is cleaned to remove surface impurities.

[0161] The gasket structure 2 is prepared by a melt pouring method to form an integrally formed composite gasket structure 2.

[0162] The fusion layer 14 and the intermediate layer 12 are prepared by a vapor deposition method, so that stable adhesion on the surface of the base body can be achieved.

[0163] The finishing process such as cutting, polishing, sand blasting, etc. can ensure the surface smoothness and geometric accuracy of the base body, which lays a foundation for the preparation of the subsequent adhesion layer, and this surface treatment process is beneficial to improve the bonding force between the base body structure 11 and the adhesion layer.

[0164] The spraying of the surface layer 13 and the design of the anchor hole 121 can prepare a low-friction nitrogen-containing high-carbon nanocrystalline coating on the surface of the intermediate layer 12. The anchor hole 121 is drilled on the intermediate layer 12, so that the material of the surface layer 13 enters the anchor hole 121, thereby enhancing the bonding stability between the two.

[0165] In order to ensure that the fusion layer 14 of the base body structure 11 of the action part 101 and the connecting part 102 is subjected to cladding treatment, so as to ensure that the gas deposition operation of the exposed part is stably carried out, the following technical solutions are provided.

[0166] The cladding shell is made of high-temperature-resistant material, and the steps of cladding treatment and removing the cladding shell include:

[0167] S3-1: The cladding shell is assembled on the outer side of the base body structure 11 of the action part 101 or the outer side of the fusion layer 14 of the connecting part 102 in a detachable manner;

[0168] S3-2: The cladding shell on the outer side of the base body structure 11 of the action part 101 or the outer side of the fusion layer 14 of the connecting part 102 is removed.

[0169] The detachable protective shell can effectively protect the internal structure, and facilitate the removal of the internal structure for vapor deposition and preparation of the outer layer structure. Embodiment 7

[0170] In order to verify the superiority of the low-friction-coefficient titanium alloy artificial bone joint in mechanical properties, biocompatibility and low-friction coefficient in the scheme of the application, the following comparative experiments are designed, and the existing titanium alloy artificial bone joint and the artificial bone joint provided by the application are tested in detail. The specific experimental process and test data are as follows:

[0171] Group A sample: The titanium alloy artificial bone joint commonly used on the market is used as a control group sample.

[0172] Group B sample: A low-friction-coefficient titanium alloy artificial bone joint provided by the application is used, wherein:

[0173] The base body structure includes the following raw material components in weight fraction:

[0174] Titanium: 85%, Nitrogen: 6%, Aluminum: 5%, Vanadium: 2%, Iron: 0.25%, Zirconium: ≤0.25%, Molybdenum: 1.5%.

[0175] The fusion layer includes the following raw material components in percentage by weight:

[0176] Titanium: 85%, Bioactive glass: 15%;

[0177] The bioactive glass includes the following raw material components in percentage by weight:

[0178] Silicon dioxide: 50%, Calcium oxide: 30%, Sodium oxide: 15%, Phosphorus oxide: 5%.

[0179] The intermediate layer includes the following raw material components in percentage by weight:

[0180] Titanium: 90%, Tantalum: 5%, Niobium: 3%, Ceramic matrix composite: 2%.

[0181] The ceramic matrix composite includes the following raw material components in percentage by weight:

[0182] Aluminum oxide: 75%, Zirconium oxide: 20%, Additive: 5%. The additive is silicon dioxide.

[0183] The surface layer is a nitrogen-containing high-carbon nanocrystalline titanium alloy coating, which includes the following raw material components in percentage by weight:

[0184] Nanocrystalline titanium: 90%, Nitrogen: 7%, Carbon: 3%.

[0185] The liner structure includes the following raw material components in percentage by weight:

[0186] Polyether ether ketone: 90%, Tetrafluoroethylene fiber: 10%.

[0187] The complete joint and the liner structure are processed according to the preparation method provided in Example 6.

[0188] The following experiments are performed on the A group samples and the B group samples:

[0189] 1. Mechanical property test: The tensile strength, yield strength and hardness of the two titanium alloy artificial bone joints are tested using a universal testing machine.

[0190] 2. Biocompatibility test: The cytotoxicity and cell proliferation of the two titanium alloy artificial bone joints are evaluated using in vitro cell culture method.

[0191] 3. Low friction coefficient test: The friction coefficient of the two titanium alloy artificial bone joints is tested using a friction and wear testing machine.

[0192] The detection data of the A group sample and the B group sample are compared:

[0193] Performance indicators Group A samples Group B samples Tensile strength (MPa) 850 950 Yield strength (MPa) 800 920 Hardness (HV) 320 380 Cytotoxicity Moderate Low Cell proliferation rate (%) 75 95 Friction coefficient 0.35 0.20

[0194] The detection data of the A group sample and the B group sample are analyzed:

[0195] 1. Mechanical properties:

[0196] The tensile strength of the titanium alloy artificial bone joint provided in the application is 950 MPa, which is about 12% higher than the existing 850 MPa.

[0197] The yield strength of the titanium alloy artificial bone joint provided in the application is 920 MPa, which is about 15% higher than the existing 800 MPa.

[0198] The hardness of the titanium alloy artificial bone joint provided in the application is 380 HV, which is about 19% higher than the existing 320 HV.

[0199] 2. Biocompatibility:

[0200] The titanium alloy artificial bone joint provided in the application shows low toxicity in the cytotoxicity test, while the existing titanium alloy artificial bone joint shows moderate toxicity.

[0201] In terms of cell proliferation rate, the titanium alloy artificial bone joint provided in the application is 95%, which is about 27% higher than the existing 75%.

[0202] 3. Low friction coefficient:

[0203] The friction coefficient of the titanium alloy artificial bone joint provided in the application is 0.20, which is significantly lower than the existing titanium alloy artificial bone joint of 0.35, with a reduction of about 43%.

[0204] 4. Conclusion:

[0205] From the above comparative experiments, it can be seen that the low friction coefficient titanium alloy artificial bone joint provided in the application is superior to the existing titanium alloy artificial bone joint in terms of mechanical properties, biocompatibility and low friction coefficient, which embodies the significant advantages of the application scheme.

[0206] It will be obvious to a person skilled in the art that the application is not limited to the details of the foregoing exemplary embodiments and can be implemented in other concrete forms without departing from the spirit or essential characteristics of the application. The embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the application being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. No reference signs in the claims should be considered as limiting the scope of the claims to the identity of the reference signs therein.

[0207] Furthermore, it should be understood that although the description is made on the basis of the embodiments, not every embodiment contains only one independent technical solution, and the description of the specification is only for the sake of clarity, and those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that those skilled in the art can understand.

Claims

1. A method for preparing a low-friction titanium alloy artificial bone joint, characterized in that: The application relates to a joint piece (1) and a gasket structure (2) arranged at the joint of adjacent joint pieces (1), wherein the joint piece (1) comprises an action part (101) and a connecting part (102), the action part (101) is combined with the gasket structure (2), and the connecting part (102) is fixedly connected with natural bones or artificial bones. The action part (101) and the connecting part (102) both comprise a base structure (11) arranged at the inner side, the action part (101) further comprises an intermediate layer (12) attached to the outer side of the base structure (11) and a surface layer (13) attached to the outer side of the intermediate layer (12), and the connecting part (102) further comprises a fusion layer (14) attached to the outer side of the base structure (11). The intermediate layer (12) is uniformly provided with anchor holes (121) on the side facing the gasket structure (2). The application further discloses a preparation method of the joint piece (1), which comprises the following steps: S1-1, preparation of the base structure (11): S1-1-1: a blank is prepared by adopting a melting casting method; S1-1-2: the surface of the blank is sequentially subjected to cutting finishing, corner polishing treatment, sand blasting treatment and cleaning to obtain the base structure (11) with the connecting part (102) and the action part (101); S1-2, preparation of the fusion layer (14): S1-2-1: the base structure (11) of the action part (101) is subjected to cladding treatment, an outer cladding shell is additionally arranged outside the action part (101), and the fusion layer (14) is prepared on the outer surface of the base structure (11) of the connecting part (102) by adopting a gas phase deposition method; S1-2-2: the outer cladding shell of the action part (101) is removed, and the base structure (11) of the action part (101) is cleaned; S1-3, preparation of the intermediate layer (12): S1-3-1: the fusion layer (14) of the connecting part (102) is subjected to cladding treatment, an outer cladding shell is additionally arranged outside the fusion layer (14), and the intermediate layer (12) is prepared on the outer surface of the base structure (11) of the action part (101) by adopting a gas phase deposition method; S1-3-2: holes are drilled on the side of the intermediate layer (12) facing the gasket structure (2) to process the anchor holes (121), the surface layer (13) is prepared on the outer surface of the intermediate layer (12) by adopting a spraying process, and the surface layer (13) enters the anchor holes (121) to enhance the bonding stability of the surface layer (13) and the intermediate layer (12); S1-3-3: the outer cladding shell of the fusion layer (14) is removed, and the whole joint piece (1) is cleaned to complete the preparation of the joint piece (1); The application further discloses a preparation method of the gasket structure (2), which comprises the following steps: S2: an integrally-formed gasket structure (2) is prepared by adopting a melting pouring method; The cladding shell is made of high-temperature-resistant material, and the cladding treatment and the step of removing the cladding shell comprise the following steps: S3-1: the cladding shell is assembled on the outer side of the base structure (11) of the action part (101) or the outer side of the fusion layer (14) of the connecting part (102) in a detachable manner. S3-2: Remove the cladding shell outside the base structure (11) of the action part (101) or the fusion layer (14) of the connecting part (102).

2. The method for preparing a low-friction coefficient titanium alloy artificial bone joint according to claim 1, characterized in that, The base structure (11) comprises the following raw material components in proportion by weight fraction: Titanium: ≥85%, Nitrogen: 5-10%, Aluminum: 2-8%, Vanadium: 1-2%.

3. The method for preparing a low-friction coefficient titanium alloy artificial bone joint according to claim 2, characterized in that, The base structure (11) further comprises the following raw material components in proportion by weight fraction: Iron: ≤0.25%, Zirconium: ≤0.3%, Molybdenum: ≤1.5%.

4. The method for preparing a low-friction coefficient titanium alloy artificial bone joint according to claim 2, characterized in that, The fusion layer (14) comprises the following raw material components in proportion by weight fraction: Titanium: 85-90%, Bioactive glass: 10-15%; The bioactive glass comprises the following raw material components in proportion by weight fraction: Silicon dioxide: 45-52%, Calcium oxide: 25-30%, Sodium oxide: 10-15%, Phosphorus oxide: 2-6%.

5. The method for preparing a low-friction coefficient titanium alloy artificial bone joint according to claim 2, characterized in that, The intermediate layer (12) comprises the following raw material components in proportion by weight fraction: Titanium: 85-95%, Tantalum: 5-10%, Niobium: 1-5%, Ceramic matrix composite: ≤5%; The ceramic matrix composite comprises the following raw material components in proportion by weight fraction: Aluminum oxide: 70-80%, Zirconium oxide: 20-30%, Additives: ≤5%; The additives include one or more of silicon dioxide, titanium oxide, and rare earth oxides.

6. The method for preparing a low-friction coefficient titanium alloy artificial bone joint according to claim 5, characterized in that, The surface layer (13) adopts a nitrogen-containing high-carbon nanocrystalline titanium alloy coating, which comprises the following raw material components in proportion by weight fraction: Nanocrystalline titanium: ≥80%, Nitrogen: 4-8%, Carbon: 2-5%.

7. The method for preparing a low-friction coefficient titanium alloy artificial bone joint according to claim 1, characterized in that, The gasket structure (2) comprises the following raw material components in proportion by weight fraction: Polyether ether ketone: 90-95%, Tetrafluoroethylene fiber: 5-10%.

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