A high-strength, wear-resistant, and corrosion-resistant titanium-steel composite plate and a preparation method thereof

Abstract

The present invention provides a high-strength, wear-resistant and corrosion-resistant titanium-steel composite plate and a preparation method thereof. The titanium-steel composite plate comprises: a steel layer and a titanium layer connected up and down, wherein the length ratio and the width ratio of the steel layer and the titanium layer are both 1, and the thickness ratio is 0.5-5. The raw material for assembling the steel layer is a medium-low carbon martensitic stainless steel plate, and the raw material for assembling the titanium layer is an industrial titanium plate. The present invention realizes the rolling composite of high-strength, corrosion-resistant martensitic stainless steel and pure titanium by reasonably assembling and rolling temperature control, optimizing the rolling process, controlling the diffusion of alloy elements at the interface and the formation of intermetallic compounds.

Description

[Technical field]

[0001] The invention relates to the technical field of titanium steel composite plate preparation, and in particular to a high-strength, wear-resistant, and corrosion-resistant titanium steel composite plate and a preparation method thereof. [Background technology]

[0002] Steel has good mechanical properties and machinability, and its cost is relatively low, but its corrosion resistance is average; titanium has high specific strength and excellent corrosion resistance, but its cost is high, especially when used as a structural component, the economic issue is worth considering. Titanium / steel composite combines steel and titanium in a reasonable way, which not only obtains the performance advantages of both materials, but also reduces the cost of components. It has gradually become a substitute for single titanium and is widely used in civil and defense industries such as petroleum, chemical industry and marine engineering.

[0003] The main preparation methods of titanium steel composite plates are: explosion composite method, diffusion composite method, explosion composite-rolling method and rolling composite method. However, the process of the explosion composite method is relatively complicated, there are many factors that affect the bonding strength of the composite plate, and it consumes a lot of energy, pollutes the environment, and has a relatively low yield rate. The composite plates produced by the diffusion composite method are small in size and cannot meet the user's requirements for large-size plates. Due to the continuous iteration and upgrading of large-tonnage rolling mills and the continuous advancement of rolling technology for large-size composite plates, it is now possible to produce large-size titanium steel composite plates by rolling, which will greatly reduce the cost of titanium steel composite plates.

[0004] CN105080997A discloses a method for preparing a titanium-steel composite plate without an intermediate layer, CN104624644A discloses a method for producing a titanium-steel composite plate, and CN105107841A discloses a method for preparing a titanium-steel composite plate. The above three patent documents all adopt titanium-steel direct composite rolling technology to prepare titanium-steel composite plates. The preparation process is simple, no intermediate layer is added, and the possibility of micropores generated after the interface compound is broken is reduced by a higher final rolling temperature, thereby improving the bonding strength of the interface. CN 109692873 A discloses a thin composite titanium-steel composite plate and a preparation method thereof, wherein the substrate is ordinary carbon steel or low alloy steel with C≤0.22%; the titanium composite material is industrial pure titanium TA2. The rolling effect is good, and a good composite of titanium steel is achieved.

[0005] In summary, a lot of research has been carried out on the preparation of titanium steel composite plates and many results have been achieved. However, the base materials of these composite plates are mostly plain carbon steel or low alloy steel, while the composite materials are mostly industrial pure titanium TA1 and TA2. Plain carbon steel or low alloy steel usually has low strength (HRC≤25) and poor corrosion resistance, which will limit its application in marine engineering, outdoor and other fields, greatly reducing the development and promotion of high-end titanium steel composite products (such as titanium steel composite armor plates with steel side hardness HRC≥50).

[0006] Therefore, in order to further broaden the application scenarios of titanium-steel composite plates, it is urgently necessary to develop a high-strength, wear-resistant and corrosion-resistant titanium-steel composite plate and a preparation method thereof to address the deficiencies of the existing technology and to solve or alleviate one or more of the above problems. [Summary of the invention]

[0007] In view of this, the present invention provides a high-strength, wear-resistant and corrosion-resistant titanium-steel composite plate and a preparation method thereof, and particularly relates to a method for producing a high-hardness, wear-resistant and corrosion-resistant double-layer titanium-steel composite plate using rolling technology and a process method thereof, by reasonably controlling the blanking and rolling temperature, optimizing the rolling process, controlling the diffusion of alloy elements at the interface and the formation of intermetallic compounds, and realizing the rolling composite of high-strength, corrosion-resistant martensitic stainless steel and pure titanium.

[0008] On the one hand, the present invention provides a high-strength, wear-resistant and corrosion-resistant titanium-steel composite plate, comprising: a steel layer and a titanium layer connected up and down, the length ratio and width ratio of the steel layer and the titanium layer are both 1, and the thickness ratio is 0.5-5, the raw material for the steel layer is a medium-low carbon martensitic stainless steel plate, and the raw material for the titanium layer is an industrial titanium plate.

[0009] According to the above aspects and any possible implementation, an implementation is further provided, wherein the medium-low carbon martensitic stainless steel plate comprises one or more of 12Cr12, 20Cr13, 30Cr13, 30Cr13N and 40Cr13.

[0010] According to the above aspects and any possible implementation, an implementation is further provided, wherein the industrial titanium plate comprises one or more of TA1, TA2, TC4 and Ti-55531.

[0011] According to the above aspects and any possible implementation, an implementation is further provided, wherein the steel layer has a length of 0.5 to 2 m, a width of 0.2 to 1 m, and a thickness of 10 to 30 mm.

[0012] According to the above aspects and any possible implementation, an implementation is further provided, wherein the titanium material layer has a length of 0.5 to 2 m, a width of 0.2 to 1 m, and a thickness of 5 to 20 mm.

[0013] According to the aspects described above and any possible implementation method, an implementation method is further provided, wherein the titanium-steel composite plate also includes a coating layer and an isolation layer, the coating layer includes an upper plate layer, a lower plate layer and four peripheral side plate layers, the upper plate layer is connected to the steel layer through the isolation layer, the lower plate layer is connected to the titanium layer through the isolation layer, and the four peripheral side plate layers are respectively coated on the four peripheral sides of the upper and lower connected steel layer and titanium layer.

[0014] According to the aspects described above and any possible implementation method, an implementation method is further provided, wherein the coating layer is ordinary carbon steel A3, the length and width of the upper plate layer and the lower plate layer are 20 mm more than the steel layer, and the thickness of the upper plate layer and the lower plate layer are both 6 to 10 mm.

[0015] According to the above aspects and any possible implementation, an implementation is further provided, wherein the isolation layer is a glass fiber isolation cloth, the length and width of the isolation layer are the same as those of the steel layer, and the thickness of the isolation layer is 1 to 2 mm.

[0016] According to the above aspects and any possible implementation, a method for preparing a high-strength, wear-resistant and corrosion-resistant titanium-steel composite plate is further provided, which is used to prepare the titanium-steel composite plate, and the preparation method comprises the following steps:

[0017] S1: A coating layer, an isolation layer, a steel layer and a titanium layer are preset, wherein the coating layer is arranged outside the steel layer and the titanium layer, and the isolation layer is arranged between the steel layer and the coating layer and between the titanium layer and the coating layer;

[0018] S2: Select medium-low carbon martensitic stainless steel plates as raw materials for the steel layer, and select industrial titanium plates as raw materials for the titanium layer;

[0019] S3: Ordinary carbon steel A3 is selected as the cladding layer, and glass fiber isolation cloth is selected as the isolation layer;

[0020] S4: pre-treating the surfaces of the steel layer and the titanium layer to be in contact;

[0021] S5: assembling the composite plate in a preset manner;

[0022] S6: The gaps between the cladding layer and the steel layer and the titanium layer are completely filled with ordinary carbon steel A3, and a circular hole with a diameter of 5 to 10 mm is reserved on either side of the cladding layer to form a first composite blank;

[0023] S8: Perform multiple passes of argon arc welding on the four sides of the composite billet, with a weld depth of 15 to 20 mm. After welding, vacuum treatment is performed through the reserved holes, and the vacuum degree is less than 1×10 -2 Pa, forming a second composite blank;

[0024] S9: heating the second composite billet to 900±25°C and keeping the temperature for 2-4h, the start rolling temperature is 850±25°C, the single pass reduction rate is 15%-30%, the total reduction rate is ≥75%, the final rolling temperature is above 725°C, and air cooling is performed to room temperature to form a third composite billet;

[0025] S10: trimming, removing the sheath, and grinding the surface of the third composite blank to obtain a titanium-steel composite plate with a thickness of 2 to 16 mm. The plate width can reach 2.5 to 3 m, and the thickness ratio of the titanium-steel layer is adjustable.

[0026] According to the above aspects and any possible implementation, an implementation is further provided, wherein the preprocessing process in S4 includes:

[0027] S41: machining the surfaces of the steel layer and the titanium layer to be in contact by a grinder to remove scales and stains on the surfaces to be in contact;

[0028] S42: Use alcohol solvent to deeply clean the surface of the machined steel layer and titanium layer and blow dry the workpiece surface.

[0029] Compared with the prior art, the present invention can achieve the following technical effects:

[0030] The rolling process of the present invention is simple, and the requirements for the raw material plate are relatively low. The width of the composite plate finally prepared can reach 2.5 to 3 m, and the thickness ratio of the titanium steel layer is adjustable. It can be used in marine engineering, outdoor and other fields, and can greatly increase the development and promotion of high-end titanium steel composite products.

[0031] Of course, any product implementing the present invention does not necessarily need to achieve all of the above-mentioned technical effects at the same time.

Brief Description of the Drawings

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 This is a method for assembling a composite plate provided by an embodiment of the present invention;

[0034] Among them, in the figure:

[0035] 1- Ordinary carbon steel A3, 2- Glass fiber isolation cloth, 3- Medium and low carbon martensitic stainless steel, 4- Titanium. [Specific implementation method]

[0036] In order to better understand the technical solution of the present invention, the embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0037] It should be clear that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0039] The present invention provides a high-strength, wear-resistant and corrosion-resistant titanium-steel composite plate, which is composed of a coating layer, an isolation layer, a steel layer and a titanium layer, wherein:

[0040] The steel layer and the titanium layer are connected up and down;

[0041] The coating layer includes an upper plate layer, a lower plate layer and four peripheral side plate layers. The upper plate layer is connected to the steel layer through an isolation layer, the lower plate layer is connected to the titanium layer through an isolation layer, and the four peripheral side plate layers are respectively coated on the four peripheral sides of the upper and lower connected steel layer and titanium layer.

[0042] The length ratio and width ratio of the steel layer and the titanium layer are both 1, and the thickness ratio is 0.5-5. The raw material for the steel layer is a medium-low carbon martensitic stainless steel plate, and the raw material for the titanium layer is an industrial titanium plate.

[0043] The medium-low carbon martensitic stainless steel plate includes one or more of 12Cr12, 20Cr13, 30Cr13, 30Cr13N and 40Cr13.

[0044] The industrial titanium plate includes one or more of TA1, TA2, TC4 and Ti-55531.

[0045] The steel layer has a length of 0.5 to 2 m, a width of 0.2 to 1 m, and a thickness of 10 to 30 mm.

[0046] The titanium material layer has a length of 0.5 to 2 m, a width of 0.2 to 1 m, and a thickness of 5 to 20 mm.

[0047] The cladding layer is ordinary carbon steel A3, the length and width of the upper plate layer and the lower plate layer are 20 mm greater than the steel layer, and the thickness of the upper plate layer and the lower plate layer are both 6 to 10 mm.

[0048] The isolation layer is a glass fiber isolation cloth. The length and width of the isolation layer are the same as those of the steel layer. The thickness of the isolation layer is 1 to 2 mm.

[0049] The present invention also provides a method for preparing a high-strength, wear-resistant and corrosion-resistant titanium-steel composite plate, which is used to prepare the titanium-steel composite plate. The preparation method comprises the following steps:

[0050] S1: A coating layer, an isolation layer, a steel layer and a titanium layer are preset, wherein the coating layer is arranged outside the steel layer and the titanium layer, and the isolation layer is arranged between the steel layer and the coating layer and between the titanium layer and the coating layer;

[0051] S2: Select medium-low carbon martensitic stainless steel plates as raw materials for the steel layer, and select industrial titanium plates as raw materials for the titanium layer;

[0052] S3: Ordinary carbon steel A3 is selected as the cladding layer, and glass fiber isolation cloth is selected as the isolation layer;

[0053] S4: pre-treating the surfaces of the steel layer and the titanium layer to be in contact;

[0054] S5: assembling the composite plate in a preset manner;

[0055] S6: The gaps between the cladding layer and the steel layer and the titanium layer are completely filled with ordinary carbon steel A3, and a circular hole with a diameter of 5 to 10 mm is reserved on either side of the cladding layer to form a first composite blank;

[0056] S8: Perform multiple passes of argon arc welding on the four sides of the composite billet, with a weld depth of 15 to 20 mm. After welding, vacuum treatment is performed through the reserved holes, and the vacuum degree is less than 1×10 -2 Pa, forming a second composite blank;

[0057] S9: heating the second composite billet to 900±25°C and keeping the temperature for 2-4h, the start rolling temperature is 850±25°C, the single pass reduction rate is 15%-30%, the total reduction rate is ≥75%, the final rolling temperature is above 725°C, and air cooling is performed to room temperature to form a third composite billet;

[0058] S10: trimming, removing the sheath, and grinding the surface of the third composite blank to obtain a titanium-steel composite plate with a thickness of 2 to 16 mm. The plate width can reach 2.5 to 3 m, and the thickness ratio of the titanium-steel layer is adjustable.

[0059] According to the above aspects and any possible implementation, an implementation is further provided, wherein the preprocessing process in S4 includes:

[0060] S41: machining the surfaces of the steel layer and the titanium layer to be in contact by a grinder to remove scales and stains on the surfaces to be in contact;

[0061] S42: Use alcohol solvent to deeply clean the surface of the machined steel layer and titanium layer and blow dry the workpiece surface.

[0062] Embodiment 1:

[0063] Steel: 12Cr12 (mass percentage wt.%, C≤0.15%, Si≤0.5%, Mn≤1.00%, Cr: 11.5~13.0%, Ni≤0.6%, P≤0.04%, S≤0.03%), size: 200×1000×25mm.

[0064] Titanium material: pure titanium TA1 (mass percentage wt.%, H≤0.015%, O≤0.20%, Fe≤0.25%, C≤0.10%, N≤0.03%, the remainder is Ti), size: 200×1000×15mm.

[0065] The specific steps are as follows:

[0066] S1: Use a grinder to machine the contact surfaces of steel and titanium to remove scale and stains on the contact surfaces; use alcohol solvent to deeply clean the processed steel and titanium surfaces and blow dry the workpiece surface.

[0067] S2: The materials and methods of assembly are ordinary carbon steel A3, glass fiber isolation cloth, 12Cr12 martensitic stainless steel, TA1 titanium material, glass fiber isolation cloth, and ordinary carbon steel A3.

[0068] S3: The space between two ordinary carbon steel A3 is completely filled with the same material, and a circular hole with a diameter of 5 to 10 mm is left on one side for welding and sealing after vacuuming to form a composite billet; the four sides of the composite billet are subjected to multi-pass argon arc welding, and the weld depth is 15 to 20 mm. After welding, vacuum treatment is performed through the reserved hole, and the vacuum degree is less than 1×10 -2 Pa.

[0069] S4: The composite billet after welding is heated to 900±25℃ and kept warm for 2h. The rolling temperature is 850±25℃, the single pass reduction rate is 20%, the total reduction rate is ≥75%, the final rolling temperature is above 725℃, and air-cooled to room temperature.

[0070] S5: After the rolled composite plate is trimmed, the jacket is removed, and the surface is ground, a high-strength titanium-steel composite plate with a thickness of 8 mm is obtained, the plate width can reach 3.2 m, and the titanium-steel layer thickness ratio is 0.6.

[0071] Embodiment 2:

[0072] Steel: 20Cr13 (mass percentage wt.%, C: 0.16~0.25%, Si≤1.00%, Mn≤1.00%, Cr: 13.0~14.0%, Ni≤0.6%, P≤0.04%, S≤0.03%), size: 200×1000×20mm.

[0073] Titanium material: pure titanium TA1 (mass percentage wt.%, H≤0.015%, O≤0.20%, Fe≤0.25%, C≤0.10%, N≤0.03%, the remainder is Ti), size: 200×1000×15mm.

[0074] The specific steps are as follows:

[0075] S1: Use a grinder to machine the contact surfaces of steel and titanium to remove scale and stains on the contact surfaces; use alcohol solvent to deeply clean the processed steel and titanium surfaces and blow dry the workpiece surface.

[0076] S2: The materials and methods of assembly are ordinary carbon steel A3, glass fiber isolation cloth, 20Cr13 martensitic stainless steel, TA1 titanium material, glass fiber isolation cloth, and ordinary carbon steel A3.

[0077] S3: The space between two ordinary carbon steel A3 is completely filled with the same material, and a circular hole with a diameter of 5 to 10 mm is left on one side for welding and sealing after vacuuming to form a composite billet; the four sides of the composite billet are subjected to multi-pass argon arc welding, and the weld depth is 15 to 20 mm. After welding, vacuum treatment is performed through the reserved hole, and the vacuum degree is less than 1×10 -2 Pa.

[0078] S4: The composite billet after welding is heated to 900±25℃ and kept warm for 2h. The rolling temperature is 850±25℃, the single pass reduction rate is 20%, the total reduction rate is ≥75%, the final rolling temperature is above 725℃, and air-cooled to room temperature.

[0079] S5: After the rolled composite plate is trimmed, the jacket is removed, and the surface is ground, a high-strength titanium-steel composite plate with a thickness of 8 mm is obtained, the plate width can reach 3.2 m, and the titanium-steel layer thickness ratio is 0.75.

[0080] Embodiment 3:

[0081] Steel: 30Cr13N (mass percentage wt.%, C: 0.26~0.35%, Si≤1.00%, Mn≤1.00%, Cr: 12.0~14.0%, Ni≤0.6%, N≤0.1%, P≤0.04%, S≤0.03%), size: 200×1000×10mm.

[0082] Titanium material: pure titanium TC4 (mass percentage wt.%, Al≤6.00%, V≤4.00%, Fe≤0.3%, C≤0.08%, N≤0.05%, the remainder is Ti), size: 200×1000×15mm.

[0083] The specific steps are as follows:

[0084] S1: Use a grinder to machine the contact surfaces of steel and titanium to remove scale and stains on the contact surfaces; use alcohol solvent to deeply clean the processed steel and titanium surfaces and blow dry the workpiece surface.

[0085] S2: The materials and methods of assembly are ordinary carbon steel A3, glass fiber isolation cloth, 30Cr13N martensitic stainless steel, TC4 titanium material, glass fiber isolation cloth, and ordinary carbon steel A3.

[0086] S3: The space between two ordinary carbon steel A3 is completely filled with the same material, and a circular hole with a diameter of 5 to 10 mm is left on one side for welding and sealing after vacuuming to form a composite billet; the four sides of the composite billet are subjected to multi-pass argon arc welding, and the weld depth is 15 to 20 mm. After welding, vacuum treatment is performed through the reserved hole, and the vacuum degree is less than 1×10- 2 Pa.

[0087] S4: The composite billet after welding is heated to 900±25℃ and kept warm for 2h. The rolling temperature is 850±25℃, the single pass reduction rate is 20%, the total reduction rate is ≥75%, the final rolling temperature is above 725℃, and air-cooled to room temperature.

[0088] S5: After the rolled composite plate is trimmed, the jacket is removed, and the surface is ground, a high-strength titanium-steel composite plate with a thickness of 8 mm is obtained, the plate width can reach 3.2 m, and the titanium-steel layer thickness ratio is 1.5.

[0089] Embodiment 4:

[0090] Steel: 40Cr13 (mass percentage wt.%, C: 0.36~0.45%, Si≤0.80%, Mn≤0.80%, Cr: 12.0~14.0%, Ni≤0.6%, P≤0.04%, S≤0.015%), size: 200×600×10mm.

[0091] Titanium material: Ti-55531 (mass percentage wt.%, Al≤5.00%, V≤5.00%, Mo≤5.00%, Cr: 3.00%, Zr≤1.0%, balance Ti), size: 200×600×20mm.

[0092] The specific steps are as follows:

[0093] S1: Use a grinder to machine the contact surfaces of steel and titanium to remove scale and stains on the contact surfaces; use alcohol solvent to deeply clean the processed steel and titanium surfaces and blow dry the workpiece surface.

[0094] S2: The materials and methods of assembly are ordinary carbon steel A3, glass fiber isolation cloth, 40Cr13 martensitic stainless steel, Ti-55531 titanium material, glass fiber isolation cloth, and ordinary carbon steel A3.

[0095] S3: The space between two ordinary carbon steel A3 is completely filled with the same material, and a circular hole with a diameter of 5 to 10 mm is left on one side for welding and sealing after vacuuming to form a composite billet; the four sides of the composite billet are subjected to multi-pass argon arc welding, and the weld depth is 15 to 20 mm. After welding, vacuum treatment is performed through the reserved hole, and the vacuum degree is less than 1×10 -2 Pa.

[0096] S4: The composite billet after welding is heated to 900±25℃ and kept warm for 2h. The rolling temperature is 850±25℃, the single pass reduction rate is 20%, the total reduction rate is ≥75%, the final rolling temperature is above 725℃, and air-cooled to room temperature.

[0097] S5: After the rolled composite plate is trimmed, the jacket is removed, and the surface is ground, a high-strength titanium-steel composite plate with a thickness of 6 mm is obtained, the plate width can reach 3.2 m, and the titanium-steel layer thickness ratio is 2.0.

[0098] The above is a detailed introduction to a high-strength, wear-resistant and corrosion-resistant titanium-steel composite plate and its preparation method provided in the embodiments of the present application. The description of the above embodiments is only used to help understand the method and its core idea of ​​the present application; at the same time, for those skilled in the art, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

[0099] For example, certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that hardware manufacturers may use different nouns to refer to the same component. This specification and claims do not use differences in names as a way to distinguish components, but use differences in the functions of components as the criteria for distinction. As mentioned throughout the specification and claims, "including" and "comprising" are open-ended terms, so they should be interpreted as "including / including but not limited to". "Approximately" means that within an acceptable error range, those skilled in the art can solve the technical problem within a certain error range and basically achieve the technical effect. The subsequent description of the specification is a preferred embodiment of the present application, but the description is for the purpose of illustrating the general principles of the present application, and is not used to limit the scope of the present application. The scope of protection of the present application shall be determined by the definition of the attached claims.

[0100] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a product or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such a product or system. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the product or system including the elements.

[0101] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0102] The above description shows and describes several preferred embodiments of the present application, but as mentioned above, it should be understood that the present application is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the application concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art do not deviate from the spirit and scope of the present application, and should be within the scope of protection of the claims attached to the present application.

Claims

1. A method for preparing a high-strength, wear-resistant and corrosion-resistant titanium-steel composite plate, characterized in that: The preparation method comprises the following steps: S1: A coating layer, an isolation layer, a steel layer and a titanium layer are preset, wherein the coating layer is arranged outside the steel layer and the titanium layer, and the isolation layer is arranged between the steel layer and the coating layer and between the titanium layer and the coating layer; S2: Select medium-low carbon martensitic stainless steel plates as raw materials for the steel layer, and select industrial titanium plates as raw materials for the titanium layer; The medium-low carbon martensitic stainless steel plate includes one or more of 12Cr12, 20Cr13, 30Cr13, 30Cr13N and 40Cr13; The industrial titanium plate includes one or more of TA1, TA2, TC4 and Ti-55531; S3: Ordinary carbon steel A3 is selected as the cladding layer, and glass fiber isolation cloth is selected as the isolation layer; S4: pre-treating the surfaces of the steel layer and the titanium layer to be in contact; S5: assembling the composite plate in a preset manner; S6: The gaps between the cladding layer and the steel layer and the titanium layer are completely filled with ordinary carbon steel A3, and a circular hole with a diameter of 5 to 10 mm is reserved on either side of the cladding layer to form a first composite blank; S7: Perform multiple passes of argon arc welding on the four sides of the first composite billet, with a weld depth of 15-20 mm. After welding, vacuum treatment is performed through the reserved holes, and the vacuum degree is less than 1×10 -2 Pa, forming a second composite blank; S8: heating the second composite billet to 900±25°C and keeping the temperature for 2-4h, the start rolling temperature is 850±25°C, the single pass reduction rate is 15%-30%, the total reduction rate is ≥75%, the final rolling temperature is above 725°C, and air cooling is performed to room temperature to form a third composite billet; S9: trimming, removing the sheath, and grinding the surface of the third composite blank to obtain a titanium-steel composite plate with a thickness of 2-16 mm, the width of which can reach 2.5-3 m, and the thickness ratio of the titanium-steel layer is adjustable; The titanium-steel composite plate with a thickness of 2-16 mm comprises: a steel layer and a titanium layer connected up and down, wherein the length ratio and width ratio of the steel layer and the titanium layer are both 1, and the thickness ratio is 0.5-5; the length of the steel layer is 0.5-2 m, the width is 0.2-1 m, and the thickness is 10-30 mm; the length of the titanium layer is 0.5-2 m, the width is 0.2-1 m, and the thickness is 5-20 mm; The titanium-steel composite plate also includes a coating layer and an isolation layer, the coating layer includes an upper plate layer, a lower plate layer and four peripheral side plate layers, the upper plate layer is connected to the steel layer through the isolation layer, the lower plate layer is connected to the titanium layer through the isolation layer, and the four peripheral side plate layers are respectively coated on the four peripheral sides of the upper and lower connected steel layer and titanium layer; the length and width of the upper plate layer and the lower plate layer are 20 mm more than the steel layer, and the thickness of the upper plate layer and the lower plate layer is 6 to 10 mm; the length and width of the isolation layer are the same as those of the steel layer, and the thickness of the isolation layer is 1 to 2 mm.

2. The preparation method according to claim 1, characterized in that: The preprocessing process in S4 includes: S41: machining the surfaces of the steel layer and the titanium layer to be in contact by a grinder to remove scales and stains on the surfaces to be in contact; S42: Use alcohol solvent to deeply clean the surface of the machined steel layer and titanium layer and blow dry the workpiece surface.

Images