Titanium steel composite substrate for metal 3D printing

Abstract

The utility model relates to the technical field of metal 3D printing, and discloses a titanium steel composite substrate for metal 3D printing, which comprises a first plate piece (1), a second plate piece (2) and rivets (5), the inward surfaces of the first plate piece (1) and the second plate piece (2) are provided with grooves matched with the rivets (5), and the first plate piece (1) and the second plate piece (2) are provided with grooves matched with the rivets (5). The first plate (1) and the second plate (2) are riveted with each other through a plurality of uniformly distributed rivets (5), the first plate (1) is made of a steel plate, and the second plate (2) and the rivets (5) are made of titanium or titanium alloy plates. The titanium steel clad steel plate provided by the utility model can meet the performance requirements on the base plate in the metal 3D printing process in the aspects of thickness, strength and thermal conductivity, but the manufacturing cost is greatly reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of metal 3D printing, and in particular to a titanium-steel composite substrate for metal 3D printing. Background Art

[0002] After metal 3D-printed parts are formed and heat-treated for stress relief, they need to be separated from the substrate. This process must ensure the parts are not damaged. The cutting line should be kept away from the part's molding surface and skewed toward the substrate. Ideally, the cutting line should be as close to the substrate as possible without completely cutting through it. However, achieving this ideal state is extremely difficult, requiring high-precision equipment and operational expertise. Even with significant investment in high-precision equipment, this ideal state remains difficult to achieve. Consequently, substrates are constantly being lost during the wire cutting process. This loss can occur in two ways: first, during the separation process, the cutting line is offset from the substrate, causing a certain thickness to be removed; second, wire cutting can easily create line marks on the substrate. In either case, the substrate requires secondary milling and grinding. Over time, the substrate becomes thinner and thinner until it no longer meets the required thickness and is discarded. Discarded substrates, no longer useful, represent a significant cost penalty. Summary of the Invention

[0003] In order to overcome or alleviate one or more of the above technical problems, the purpose of the present utility model is to provide a titanium-steel composite substrate for metal 3D printing, which can be used as a substrate for metal 3D printing and can also be used in other industries or fields according to its characteristics.

[0004] The utility model provides the following technical solutions:

[0005] A titanium-steel composite substrate for metal 3D printing comprises a first plate (1), a second plate (2) and a rivet (5); the first plate (1) and the second plate (2) are provided with grooves adapted to the rivet (5) on their inwardly facing surfaces; the first plate (1) and the second plate (2) are riveted to each other via a plurality of evenly distributed rivets (5); the first plate (1) is made of a steel plate; and the second plate (2) and the rivet (5) are both made of titanium or a titanium alloy plate.

[0006] According to some embodiments, the rivet (5) and the groove are of corresponding cylindrical shapes.

[0007] According to some embodiments, the rivet (5) is provided with a solder coating on the outside, and the solder is selected from copper, copper alloy or silver.

[0008] According to some embodiments, the second plate member (2) and the first plate member (3) are provided with the soldering sheet (3) for soldering, the soldering sheet (3) is provided with a through hole matched with the rivet (5), and the soldering sheet (3) is made of copper, copper alloy or silver.

[0009] According to some embodiments, the first plate member (1) is connected to the second plate member (2) on the left and right sides through soldering and riveting of the rivet (5).

[0010] According to some embodiments, the rivet (5) is in a conical shape, the larger side of the cross section of the conical shape is the first plate member (1), the fourth plate member (4) is arranged between the soldering sheet (3) and the first plate member (1), the fourth plate member (4) is provided with a conical hole matched with the rivet (5), another soldering sheet (3) is arranged between the fourth plate member (4) and the first plate member (1), the fourth plate member (4) is made of steel plate, and the first plate member (1), the fourth plate member (4) and the second plate member (3) are connected through soldering and riveting of the rivet (5).

[0011] Compared with the prior art, the utility model has the advantages of the following beneficial effects:

[0012] The titanium-steel composite substrate for metal 3D printing has lower cost than the prior art substrate, is less likely to be brittle and broken through riveting of the uniformly distributed rivet or the brazing technology between the titanium or titanium alloy plate and the steel plate, and is adjusted from titanium material to ordinary carbon steel plate after substrate loss and abandonment, so that cost loss is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 FIG. 1 is a schematic view of a titanium-steel composite substrate for metal 3D printing according to an embodiment of the utility model.

[0014] Figure 2 FIG. 2 is a sectional view of the titanium-steel composite substrate for metal 3D printing. Figure 1

[0015] Figure 3 FIG. 3 is an exploded view of a titanium-steel composite substrate for metal 3D printing according to an embodiment of the utility model.

[0016] Figure 4 FIG. 4 is an exploded view of a left-right symmetrical titanium-steel composite substrate for metal 3D printing according to an embodiment of the utility model.

[0017] ​Figure 5 This is a schematic diagram of a titanium-steel composite substrate for metal 3D printing provided in Example 3 of the present utility model.

[0018] Figure 6 for Figure 5 sectional view of .

[0019] Figure 7 for Figure 5 Exploded diagram.

[0020] In the picture:

[0021] First plate 1; second plate 2; welding piece 3; fourth plate 4; rivet 5. DETAILED DESCRIPTION

[0022] The present invention is described in detail below with reference to the following embodiments and accompanying drawings. However, it should be understood that the embodiments and accompanying drawings are merely illustrative of the present invention and do not limit the scope of protection of the present invention. All reasonable variations and combinations within the scope of the present invention are intended to fall within the scope of protection of the present invention.

[0023] At high temperatures, titanium and its alloys absorb large amounts of gases such as oxygen, helium, and hydrogen, causing them to become brittle and even produce pores. The solubility of steel in titanium is very low, and intermetallic compounds are easily formed in the weld during welding. When welded to stainless steel, titanium forms even more complex intermetallic compounds with iron, chromium, and nickel, resulting in a serious decrease in the plasticity of the weld, increased brittleness, and even the formation of cracks and pores. Furthermore, because the thermal conductivity of titanium and its alloys is approximately 1 / 6 of that of steel, and their elastic modulus is 1 / 2 that of steel, they are very susceptible to deformation during welding.

[0024] Titanium and its alloys have poor welding properties and low plasticity on the weld surface. Volume expansion during welding generates large internal stresses, leading to cold cracks. In addition, because the longitudinal elastic modulus of titanium and its alloys is smaller than that of conventional metals (such as stainless steel and carbon steel), under the same welding action, the titanium alloy will deform more and be difficult to correct.

[0025] Cold cracks generated during welding are the root cause of brittle fracture. Brittle fracture consumes far less energy than ductile fracture and is characterized by low-stress failure. It propagates automatically through the release of elastic energy stored within the structure, leading to damage. Consequently, visible plastic deformation is rarely observed. Fracture occurs suddenly without obvious warning signs, resulting in the scrapping of the workpiece.

[0026] To avoid brittle fracture of titanium and titanium alloys during the composite process with steel, three preventive measures are taken. These three preventive measures are explained below with reference to examples and accompanying drawings.

[0027] Example 1

[0028] In this embodiment, rivets are used to rivet substrates made of two materials.

[0029] like Figures 1-2 This embodiment provides a titanium-steel composite substrate for metal 3D printing. The substrate comprises a first plate 1 and a second plate 2. The inwardly facing surfaces of the first and second plates 1 and 2 are each provided with grooves adapted for rivets 5. The first and second plates 1 and 2 are riveted together using evenly spaced rivets 5 and grooves. The first plate 1 is made of steel, and the second plate 2 is made of titanium or a titanium alloy. The rivets 5 are made of titanium or a titanium alloy.

[0030] In metal 3D printing, high-temperature metal powder is deposited layer by layer on a substrate, forming a solid component. During this process, the substrate must be able to withstand the high temperatures generated by the laser beam. To prevent the extremely high temperatures from causing stress and deformation in the substrate, the substrate requires a certain thickness (typically 20-300 mm). In this embodiment, a pre-assembled steel plate and titanium or titanium alloy plate are combined to replace the original single titanium substrate to reduce costs. However, due to the different expansion systems and densities of steel and titanium alloy, their contraction ratios also differ. While ensuring good thermal conductivity of the composite substrate, preventing deformation of the composite substrate and addressing the brittleness of titanium and steel after welding, this embodiment utilizes a combination of riveting, diffusion bonding, brazing, and thermal conductivity to effectively connect the two materials and achieve thermal conductivity and tensile strength. Riveting is a key technique. The contact surfaces of the titanium or titanium alloy plate and the steel plate are each provided with evenly spaced cylindrical grooves. Metal cylinders serve as rivets, placed within the grooves. The rivets are made of either titanium or a titanium alloy, which can be the same material as the titanium substrate or a different material. During the welding process, the rivet heats and expands, constrained by the hole in which it is located. The holding force of the surface corresponding to the hole increases, diffuses, and connects, providing radial mechanical support to the upper and lower substrates of different materials. Even if the diffusion bond strength is insufficient and the rivet deforms at high temperatures, its sufficient restraint ensures that it cannot be pulled out. Riveting prevents substrate migration and stretching, combining mechanical force and thermal conductivity to ensure a secure connection between titanium or titanium alloy plates and steel plates.

[0031] Due to the limited hole size, the rivet's expansion is limited. Although microscopic cracks may occur at the intergranular interface, the internal mechanical strength remains. Equidistantly spaced rivets on the weld plane ensure even distribution of riveting force, effectively preventing thermal deformation of the composite substrate.

[0032] The rivets are coated with various materials that can be used as brazing materials, such as copper, copper alloy or silver. These coatings firmly connect the rivets to the titanium or titanium alloy plates and steel plates during the diffusion welding process.

[0033] Example 2

[0034] This embodiment adopts brazing technology.

[0035] like Figure 3 , this embodiment provides a titanium-steel composite substrate for metal 3D printing, which includes a first plate 1, a second plate 2 and a welding piece 3. The inward surfaces of the first plate 1 and the second plate 2 are provided with grooves adapted to the rivets 5, and the first plate 1 and the second plate 2 are riveted to each other through evenly distributed rivets 5 and grooves. The material of the first plate 1 is selected from steel plate, and the material of the second plate 2 is selected from titanium or titanium alloy plate. The material of the rivet 5 is selected from titanium or titanium alloy. The difference from Example 1 is that this embodiment is provided with a welding piece 3 between the second plate 2 and the rivet 5, and a conical hole adapted to the rivet 5 is provided on the welding piece 3, which is made of brazing material. The rivet 5 is coated with brazing material, and the brazing material is copper, copper alloy or silver or other materials.

[0036] When titanium and steel are directly welded, metal compounds will be produced and severe embrittlement will occur. Therefore, this embodiment adopts a brazing process to manufacture a composite substrate. The welding sheet 3 is laid between the first and second plates. During the brazing heating process, the brazing material melts, fills the gap between the plates, infiltrates the upper and lower plates, and diffuses with them, achieving the purpose of connecting the titanium or titanium alloy plate and the steel plate into one. Similarly, during the brazing process. The brazing material coating wrapped around the rivet also plays the role mentioned above, further welding the titanium or titanium alloy plate, rivet and steel plate together. That is, the titanium or titanium alloy plate and the steel plate are riveted by rivets and welded by brazing, ensuring that the substrates of the two materials are perfectly combined.

[0037] In this embodiment, the weld surface of the first plate 1 is milled using a disc milling process. The cutter disc is tilted relative to the guide rail, making it difficult to ensure that the tips of each blade are aligned. The resulting surface is not perfectly flat, but rather rough, with visible machined lines. This surface roughness is ideal for melting and leveling the brazing filler metal of equal thickness, and provides improved mechanical adhesion to the plate surface after cooling.

[0038] In summary, the first and second plates and the rivet can be firmly welded together through brazing, and the process is simple, reliable and low in cost.

[0039] This processing method can also be used to produce double-sided titanium or titanium alloy substrates according to the special needs of customers. Figure 4 As shown, the left and right sides are second plates 2 and inward-facing welding pieces 3, which are connected to a first plate 1 in the middle by brazing and riveting with rivets 5 on both sides.

[0040] Example 3

[0041] This embodiment is a solution for strengthening the composite substrate.

[0042] In order to meet the needs of customers with higher strength requirements, this embodiment can also be made into a reinforced composite substrate. Figures 5-7This embodiment provides a titanium-steel composite substrate for metal 3D printing, comprising a first plate 1, a second plate 2, and a welding piece 3. The inwardly facing surfaces of the first and second plates 1, 2 are each provided with a groove adapted for a rivet 5. The welding piece 3 is provided with a through-hole adapted for the rivet 5. The first and second plates 1, 2 are tightly connected by brazing, uniformly distributed rivets 5, and the groove. The first plate 1 is made of a steel plate, and the second plate 2 is made of a titanium or titanium alloy plate. The rivet is made of a titanium or titanium alloy. The welding piece 3 is made of a brazing filler metal, which is coated with a brazing filler metal film. The brazing filler metal is made of copper, a copper alloy, or other materials.

[0043] The difference from the second embodiment is that the rivet 5 is in the shape of a cone, and the side with the larger cross-sectional area of ​​the cone is the first plate 1; Figure 7 A fourth plate 4 is added between the welding lug 3 and the rivet 5 near the side of the second plate 2. The fourth plate 4 has a tapered hole that fits the rivet 5. The fourth plate 4 is made of steel, and another welding lug 3 is placed between the rivet 5 and the first plate 1. The fourth plate 4 has a tapered hole of the same size as the rivet 5. The larger diameter of the tapered hole mates with the first plate 1, securing the tapered rivet 5 therein and preventing it from falling out of the fourth plate 4.

[0044] Compared with Example 2, the adjustments in this example include:

[0045] (1) One end of the rivet 5 is changed to a conical structure to increase the contact surface between the rivet 5 and the steel plate of the first plate 1.

[0046] (2) To accommodate the change in shape of the rivet column, the steel base plate is designed as a double-layer structure, with a tapered hole in the upper layer to accommodate the rivet. During the brazing process of the upper and lower steel plates, the rivet is fixed between the two plates. Due to the inverted cone shape, the rivet is more difficult to pull out during the brazing process.

[0047] The above two adjustments increase the mechanical holding force of the rivet and the strength of the composite substrate. The other processes for strengthening the composite plate are the same as those for the cylindrical titanium alloy riveted composite substrate mentioned above.

[0048] In order to control manufacturing costs, the material of the second plate 2 can be selected to be thinner as needed.

[0049] The technology of the present invention can also be expanded in occasions and products with similar scene requirements, such as chimney panels and various pipelines in chemical plants, etc.

[0050] The above embodiments are merely preferred implementations of the present invention, and the scope of protection of the present invention is not limited to the above embodiments. All technical solutions based on the principles of the present invention are within the scope of protection of the present invention. It should be noted that improvements and modifications that can be made by persons of ordinary skill in the art without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A titanium-steel composite substrate for metal 3D printing, characterized by: The invention comprises a first plate (1), a second plate (2) and a rivet (5); the first plate (1) and the second plate (2) are provided with grooves adapted to the rivet (5) on their inward surfaces; the first plate (1) and the second plate (2) are riveted to each other by a plurality of evenly distributed rivets (5); the material of the first plate (1) is selected from steel plate; the material of the second plate (2) and the rivet (5) are selected from titanium or titanium alloy plate.

2. The titanium-steel composite substrate for metal 3D printing according to claim 1, characterized in that: The rivet (5) and the groove are correspondingly cylindrical.

3. The titanium-steel composite substrate for metal 3D printing according to claim 2, characterized in that: The rivet (5) is provided with a solder coating on the outside, and the solder is selected from copper, copper alloy or silver.

4. The titanium-steel composite substrate for metal 3D printing according to claim 1, characterized in that: A soldering sheet (3) for brazing is provided between the second plate (2) and the first plate (1), and a through hole adapted to the rivet (5) is provided on the soldering sheet (3). The soldering sheet (3) is a solder, and the solder is selected from copper, copper alloy or silver.

5. The titanium-steel composite substrate for metal 3D printing according to claim 4, characterized in that: It also includes another second plate (2) on the other side of the first plate (1) and another welding sheet (3) for brazing, and the left and right sides of the first plate (1) are tightly connected to the second plate (2) through brazing and riveting with the rivets (5).

6. The titanium-steel composite substrate for metal 3D printing according to claim 4, characterized in that: The rivet (5) is in the shape of a cone, and the side with the larger cross-sectional area of ​​the cone is the first plate (1); a fourth plate (4) is provided between the welding piece (3) and the first plate (1), and a conical hole adapted to the rivet (5) is provided on the fourth plate (4); another welding piece (3) is provided between the fourth plate (4) and the first plate (1), and the material of the fourth plate (4) is selected from steel plate; the first plate (1), the fourth plate (4) and the second plate (2) are tightly connected by brazing and riveting with the rivet (5).

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