Preparation method and application of powder solid hot isostatic pressing titanium-steel bimetallic part

Abstract

The invention belongs to the technical field of preparation of bimetallic materials, and relates to a preparation method and application of a powder solid hot isostatic pressing titanium-steel bimetallic part. The method comprises the steps that firstly, a steel base body is preprocessed, and a prefabricated part is obtained; then a metal material layer is arranged on the surface of the prefabricated part in advance, and a prefabricated steel base material is formed; finally, the prefabricated steel base material is put into a sheath, and titanium alloy powder is put into a gap between the sheath and the metal material layer; and then removing the sheath after hot isostatic pressing to form an intermediate base material, finally performing differential heat treatment on the intermediate base material, and removing an oxide layer to obtain the titanium-steel bimetallic part. It is ensured that the bimetallic composite material has the high hardness and wear resistance of steel and the enough structural strength of titanium alloy, and the performance cooperation problem of dissimilar metal composite components is effectively solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of the preparation of bimetallic materials, and relates to a preparation method and application of a powder-solid hot isostatic pressing titanium-steel bimetallic part. Background Art

[0002] Titanium alloys, with their remarkable properties such as high specific strength and excellent corrosion resistance, play an important and indispensable role in key fields such as aerospace, ocean engineering, energy petrochemical, etc. However, the high price of titanium alloys to a certain extent limits their wide application; in addition, in some special working environments, in order to improve the wear resistance of the working surface, preparing a special steel wear-resistant layer on the surface of titanium alloys is an effective method, which can not only improve the service performance of titanium alloys but also further expand their application scenarios. From another perspective, for special steel parts applied to high-end equipment, there is a problem of improving service performance by reducing weight, and the adoption of a partial "replacing steel with titanium" scheme can well meet the energy efficiency requirements of new equipment. To sum up, there is a strong application demand for titanium-steel bimetallic materials in many key fields.

[0003] However, there are obvious physical and chemical differences between titanium alloys and steels. The difference in their thermal expansion coefficients is large, and brittle intermetallic compounds such as FeTi and Fe2Ti are easily formed in high-temperature environments, which makes traditional welding or diffusion bonding methods extremely prone to interface failure. Although intermediate layers such as copper and nickel are used in the prior art to alleviate interface reactions, this method has disadvantages such as complex processes and insufficient bonding strength, and it is also difficult to prepare complex-shaped parts such as bimetallic rotors. In addition, the heat treatment processes of steel and titanium alloys are very different, and it is not easy to make these two materials have excellent properties simultaneously in engineering practice. Therefore, there is an urgent need for a composite process that can take into account interface bonding strength, material properties, and complex shape forming. Summary of the Invention

[0004] The purpose of the present invention is to overcome the above-mentioned disadvantages of the prior art and propose a preparation method and application of a powder-solid hot isostatic pressing titanium-steel bimetallic part.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions: A preparation method of a powder-solid hot isostatic pressing titanium-steel bimetallic part, as Figure 1 shown, includes the following steps: Step 1: First, preprocess the steel substrate to obtain a preform; then pre-place the metal material layer on the surface of the preform to form a prefabricated steel substrate; finally, place the prefabricated steel substrate into a sheath, and load titanium alloy powder into the gap between the sheath and the metal material layer; Step 2: Degas the jacket filled with titanium alloy powder, perform hot isostatic pressing on the degassed jacket, and remove the jacket after hot isostatic pressing to form an intermediate substrate. As shown in Figure 2 , the outer layer of the intermediate substrate is a steel matrix layer, the middle layer is a metal material layer, and the inner layer is a titanium alloy layer; Step 3: Perform differential heat treatment on the intermediate substrate. The differential heat treatment specifically is: while heat-treating the steel matrix layer, perform cold treatment on the titanium alloy layer; after the heat treatment is completed, cool the steel matrix layer, and the cold treatment continues until the steel matrix layer is cooled to room temperature. After the steel matrix layer is cooled to room temperature, perform tempering treatment, and then cool it to room temperature again to obtain a preform; Step 4: Remove the surface oxide layer and excess amount of the preform to obtain a titanium-steel bimetallic part.

[0006] Further, in Step 1, the surface roughness Ra of the steel matrix ≤ 3.2 μm.

[0007] Further, in Step 1, the material of the metal material layer is one or more of copper, nickel, vanadium, and niobium, and the thickness of the metal material layer is 30 μm to 180 μm.

[0008] Further, in Step 1, the particle size of the titanium alloy powder is 15 μm to 250 μm, and the sphericity ≥ 95%.

[0009] Specifically, in Step 1, the steel matrix can be carbon steel, stainless steel, die steel, high-strength steel, etc. Preprocessing the steel matrix is to process the steel matrix into a block of corresponding shape; pre-place the metal material layer on the surface of the preform. Specifically: pre-place the metal material layer on the surface of the steel matrix through processes such as PVD, laser cladding, or plasma spraying; the material of the jacket is low-carbon steel, the shape of the jacket is close to the shape of the final product, the dimensions of the jacket and the steel matrix are matched, and the gap between the jacket and the steel matrix < 2 mm; load titanium alloy powder into the gap on the side of the jacket and the metal material layer.

[0010] It should be added that the metal material layer can be pre-placed on the inner surface or the outer surface of the preform according to process requirements. From the perspective of practical operation optimization, it is preferred to set the steel matrix on the outer surface of the preform for the following reasons: 1. Heat treatment convenience: When the steel matrix is on the outer surface, local heat treatment can be directly performed on it by processes such as induction heating and laser heat treatment without additional tooling assistance, and the process path is more concise. 2. Equipment compatibility: If the steel matrix is placed on the inner surface of the preform, heat treatment equipment (such as heating coils, laser heads) may be limited by the internal space structure of the preform, resulting in ineffective contact or inaccurate temperature control. Especially for parts with complex internal cavity structures, heating blind spots or low thermal efficiency are likely to occur.

[0011] Further, in Step 2, the degassing temperature is 230°C to 480°C.

[0012] Further, in step two, the temperature of the hot isostatic pressing treatment is 760°C to 910°C, the pressure of the hot isostatic pressing treatment is 110 MPa to 160 MPa, and the time of the hot isostatic pressing treatment is 1.5 h to 4.5 h.

[0013] Specifically, in step two, the gas in the jacket is removed, and the vacuum is pumped to ≤1×10 -3 Pa, and then the degassing nozzle is sealed; the temperature of the hot isostatic pressing is 760°C to 910°C, which is lower than the β transformation temperature of the titanium alloy and the austenite transformation temperature of the steel.

[0014] Further, in step three, the steel matrix layer is heat-treated, specifically: first, the steel matrix layer is induction-heated or laser heat-treated, the temperature of the heat treatment is 800°C to 1200°C, and the holding time is 20 min to 90 min.

[0015] Further, in step three, the titanium alloy layer is cold-treated, specifically: the titanium alloy layer is cooled by compressed air, and the temperature is maintained below 500°C. The flow rate of the compressed air is 5 m / s to 15 m / s, and the temperature is 15°C to 45°C.

[0016] Further, in step three, the temperature of the tempering treatment is 200°C to 600°C, and the time is 45 min to 4 h.

[0017] It should be noted that step three mainly includes the following processes: a. The steel matrix layer is induction-heated (frequency: 10 kHz to 100 kHz) or laser heat-treated (laser power: 1.5 kW to 6 kW, scanning speed: 0.5 m / min to 6 m / min, spot size: 1 mm to 5 mm), heated to 800°C to 1200°C and then held for 20 min to 90 min; b. Synchronously, the titanium alloy part is cooled with compressed air to make its temperature ≤500°C; c. After the holding of the steel matrix layer is completed, the steel matrix layer is cooled (the cooling methods include water quenching, oil quenching, air cooling, and air cooling in air). The titanium alloy layer is kept cooled with compressed air until the steel drops to the ambient temperature; among them, the water spray flow rate in water quenching or the oil spray flow rate in oil quenching is 5 L / min to 200 L / min, and the gas flow rate of air blowing cooling is 10 m 3 / h to 100 m 3 / h; d. According to the need, the steel is tempered by induction heating (frequency 10 kHz to 100 kHz) or laser heat treatment (laser power 1.5 kW to 6 kW, scanning speed 0.5 m / min to 6 m / min, spot size 1 mm to 5 mm), and then air-cooled after tempering.

[0018] Step d is an optional step, and whether to perform step d can be determined according to the materials used for the steel substrate layer and the titanium alloy layer.

[0019] Furthermore, the shear strength at the interface between the titanium alloy and the steel is ≥280 MPa, the hardness of the steel is ≥50 HRC, and the tensile strength of the titanium alloy is ≥900 MPa.

[0020] The present invention also provides an application of a titanium-steel bimetallic part prepared by the above preparation method in the preparation of a rotating body or a special-shaped part for the fields of aerospace and ships; the special-shaped part includes complex geometric structures, such as components with inner holes and curved surfaces.

[0021] Compared with the prior art, the present invention has the following beneficial effects: First, the present invention adopts a gradient interface design. The intermediate layer realizes metallurgical bonding through PVD or laser cladding methods. The hot isostatic pressing (HIP) temperature is within 100 °C below the titanium alloy T β and does not exceed the austenite transformation temperature of the steel, which can ensure the densification of the titanium alloy and avoid the coarsening of the β phase of the titanium alloy, and at the same time does not affect the subsequent heat treatment microstructure regulation of the steel; during the hot isostatic pressing (HIP) process, by precisely controlling the process parameters, the excessive diffusion of Fe-Ti elements is inhibited, effectively avoiding the formation of brittle intermetallic compounds (IMCs), so as to ensure that the interface bonding strength ≥200 MPa (tested according to the standard of GB / T6400-2007); Second, the present invention utilizes the powder-solid bonding characteristics of the HIP process to realize near-net shaping of complex geometric structures (such as components with inner holes and curved surfaces), and the material utilization rate is greatly improved; Third, the present invention overcomes the limitation of the conventional coating process on the coating thickness (for example, micro-arc oxidation, laser cladding, PVD, etc. can only prepare coatings with a thickness of dozens of microns or a few millimeters), and can achieve a thickness of both materials reaching the order of dozens of millimeters, so as to ensure the design requirements and service performance; Fourth, the present invention adopts a zoning heat treatment method, precisely acts on the steel substrate layer through induction heating or laser heating, and at the same time uses the forced convection technology of compressed air to protect the titanium alloy layer. This forced convection technology of compressed air can avoid the phase transformation of the titanium alloy, so that the mechanical properties of the titanium alloy are hardly affected by the heat generated by the heat treatment of the steel substrate layer, thus ensuring that the bimetallic composite material has both the high hardness and wear resistance characteristics of the steel and the sufficient structural strength of the titanium alloy, effectively solving the problem of performance coordination of heterogeneous metal composite components, and is of great significance in application scenarios such as surface modification of titanium alloy components and weight reduction of steel components. Description of the Drawings

[0022] The drawings here are incorporated into the specification and form a part of this specification, and are used together with the specification to explain the principles of the present invention.

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0024] Figure 1 Schematic flow chart of the preparation method of the present invention; Figure 2 Schematic diagram of the structure of the titanium-steel bimetallic material in the present invention; Figure 3 Scanning electron microscope image of the titanium-steel bimetallic interface prepared in Example 1; Figure 4 Scanning electron microscope image of the titanium-steel bimetallic interface prepared in Example 2; Figure 5 Scanning electron microscope image of the titanium-steel bimetallic interface prepared in Example 3.

[0025] Wherein: 1 is the steel matrix layer; 2 is the metal material layer; 3 is the titanium alloy layer; 4 is the jacket. Detailed implementation manners

[0026] Here, the exemplary embodiments will be described in detail. The implementation manners described in the following exemplary embodiments do not represent all implementation manners consistent with the present invention. On the contrary, they are only examples consistent with some aspects of the present invention detailed in the appended claims.

[0027] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the drawings and embodiments.

[0028] It should be noted that the particle size of the titanium alloy powder in the following three embodiments is 15 μm to 250 μm, and the sphericity is ≥ 95%. Example 1

[0029] This embodiment provides a preparation method for a hot isostatic pressing titanium (TA15)-steel (T15) bimetallic part, which is specifically implemented according to the following steps: Step 1. First, preprocess the steel matrix to obtain a preform; then pre-place the metal material layer 2 on the surface of the preform to form a prefabricated steel substrate; finally, place the prefabricated steel substrate into the jacket 4, and fill the gap between the jacket 4 and the metal material layer 2 with titanium alloy powder; Specifically, the T15 steel (steel matrix) is processed into a cuboid groove with dimensions of 30 mm * 40 mm * 50 mm, a wall thickness of 20 mm, and a surface roughness Ra of 2.8 μm; the metal material layer 2 is made of pure vanadium, and the thickness of the metal material layer 2 is 30 μm, which is pre-placed on the surface of the T15 steel by plasma spraying; the sphericity of the TA15 titanium alloy powder is 98.3%; a low-carbon steel is used to make the jacket 4, and the jacket 4 is dimensionally matched with the steel matrix; Step 2: Degas the jacket 4 filled with titanium alloy powder, and perform hot isostatic pressing on the degassed jacket 4. After hot isostatic pressing, remove the jacket 4 to form an intermediate substrate. The outer layer of the intermediate substrate is the steel matrix layer 1, the middle layer is the metal material layer 2, and the inner layer is the titanium alloy layer 3; Specifically, degas the jacket 4 filled with titanium alloy powder. The degassing temperature is 230 °C, and the vacuum is pumped to 9.1×10 -4 Pa, and then seal the degassing nozzle; the hot isostatic pressing temperature is 910 °C, the hot isostatic pressing pressure is 130 MPa, and the hot isostatic pressing time is 1.5 h; remove the carbon steel jacket 4 by machining; Step 3: Perform differential heat treatment on the intermediate substrate. The differential heat treatment specifically is: while heat-treating the steel matrix layer 1, perform cold treatment on the titanium alloy layer 3; after the heat treatment is completed, cool the steel matrix layer 1, and the cold treatment on the titanium alloy layer 3 continues until the steel matrix layer 1 cools to room temperature to obtain a preform; Specifically, it includes the following processes: a. Perform laser heat treatment on the steel matrix layer 1 (laser power 4 kW, scanning speed 3.5 m / min, spot size 2.5 mm), heat up to 1180 °C and hold for 20 min; b. Synchronously cool the titanium alloy layer 3 with compressed air (flow rate 15 m / s, temperature 15 °C) to make its temperature ≤ 500 °C; c. After the holding of the steel matrix layer 1 ends, perform oil quenching and cooling on it, and the oil flow rate is 40 L / min. At this time, keep cooling the titanium alloy layer 3 with compressed air until the steel matrix layer 1 drops to the ambient temperature; d. Perform tempering treatment on the steel matrix layer 1 at a temperature of 570 °C for 45 min by laser heat treatment (laser power 4 kW, scanning speed 3.5 m / min, spot size 2.5 mm), and then air-cool to room temperature after tempering; Step 4: Remove the surface oxide layer and excess amount of the preform to obtain a titanium-steel bimetallic part; In this embodiment, the shear strength at the interface between the titanium alloy and the steel is ≥ 307 MPa, the steel hardness is ≥ 59 HRC, and the tensile strength of the titanium alloy is ≥ 1108 MPa. The scanning electron microscope image of the titanium-steel bimetallic interface prepared in this embodiment is as shown in Figure 3As shown, it can be seen from the figure that the titanium-steel bimetal structure is dense and the connection is intact. Example 2

[0030] This embodiment provides a method for preparing a hot isostatic pressing titanium (TC4)-steel (18Ni300) bimetal part, which is specifically implemented according to the following steps: Step 1: First, preprocess the steel substrate to obtain a preform; then pre-place the metal material layer 2 on the surface of the preform to form a prefabricated steel substrate; finally, place the prefabricated steel substrate into the jacket 4, and fill the gap between the jacket 4 and the metal material layer 2 with titanium alloy powder; Specifically, process the 18Ni300 steel (steel substrate) into a pipe with a diameter of 300 mm and a wall thickness of 10 mm, and the surface roughness Ra is 1.9 μm; the metal material layer 2 is a copper-nickel composite layer, where the thickness of the copper layer is 50 μm and the thickness of the nickel layer is 50 μm, so the thickness of the metal material layer 2 is 100 μm, and the nickel layer is in direct contact with the steel substrate and is pre-placed on the surface of the 18Ni300 steel through the PVD magnetron sputtering process; the sphericity of the TC4 titanium alloy powder is 97.2%; use low-carbon steel to make the jacket 4, and the size of the jacket 4 matches that of the steel substrate; Step 2: Degas the jacket 4 filled with titanium alloy powder, and perform hot isostatic pressing on the degassed jacket 4. After hot isostatic pressing, remove the jacket 4 to form an intermediate substrate. The outer layer of the intermediate substrate is the steel substrate layer 1, the middle layer is the metal material layer 2, and the inner layer is the titanium alloy layer 3; Specifically, degas the jacket 4 filled with titanium alloy powder. The degassing temperature is 350 °C, evacuate to 8.2×10 -4 Pa and then seal the degassing nozzle; the hot isostatic pressing temperature is 860 °C, the hot isostatic pressing pressure is 110 MPa, and the hot isostatic pressing time is 3 h; remove the carbon steel jacket 4 by machining; Step 3: Perform differential heat treatment on the intermediate substrate. The differential heat treatment is specifically: while performing heat treatment on the steel substrate layer 1, perform cold treatment on the titanium alloy layer 3; after the heat treatment is completed, cool the steel substrate layer 1, and the cold treatment on the titanium alloy layer 3 continues until the steel substrate layer 1 cools to room temperature to obtain a preform; Specifically, it includes the following processes: a. Induction heat the steel substrate layer 1 (frequency is 50 kHz), heat up to 820 °C and hold for 90 min; b. Synchronously cool the titanium alloy layer 3 with compressed air (flow rate 5 m / s, temperature 45 °C) to make its temperature ≤ 500 °C; c. After the heat preservation of the steel substrate layer 1 is completed, air-cool it. At this time, keep the compressed air cooling of the titanium alloy layer 3 until the steel substrate layer 1 drops to the ambient temperature; d. Temper the steel substrate layer 1 by induction heating (frequency: 50 kHz) at 400 °C for 4 h, and then air cool after tempering; Step 4: Remove the surface oxide layer and excess amount of the preform to obtain a titanium-steel bimetallic part; In this embodiment, the shear strength at the interface between the titanium alloy and the steel is ≥289 MPa, the hardness of the steel is ≥54 HRC, and the tensile strength of the titanium alloy is ≥921 MPa. The scanning electron microscope image of the interface of the titanium-steel bimetallic part prepared in this embodiment is as Figure 4 shown. It can be seen from the figure that the titanium-steel bimetallic structure is dense and the connection is intact. Example 3

[0031] This embodiment provides a method for preparing a hot isostatic pressing titanium (TB18)-steel (30CrMnSiNi2A) bimetallic part, which is specifically implemented according to the following steps: Step 1: First, preprocess the steel substrate to obtain a preform; then pre-place the metal material layer 2 on the surface of the preform to form a prefabricated steel substrate; finally, place the prefabricated steel substrate into the jacket 4, and load titanium alloy powder into the gap between the jacket 4 and the metal material layer 2; Specifically, process the ultra-high-strength steel (30CrMnSiNi2A) into a crucible shape with a diameter of 250 mm, a height of 300 mm, a wall thickness of 25 mm, and a surface roughness Ra of 1.2 μm; the metal material layer 2 is made of a niobium-copper-nickel composite layer, where the thickness of the niobium layer is 55 μm, the thickness of the copper layer is 70 μm, and the thickness of the nickel layer is 55 μm, so the thickness of the metal material layer 2 is 180 μm; the nickel layer is in direct contact with the steel substrate and is pre-placed on the surface of the 30CrMnSiNi2A steel by a high-speed laser cladding process; the sphericity of the TB18 titanium alloy powder is 99.2%; use low-carbon steel to make the jacket 4, and the jacket 4 is sized to fit the steel substrate; Step 2: Degas the jacket 4 filled with titanium alloy powder, and perform hot isostatic pressing on the degassed jacket 4. After hot isostatic pressing, remove the jacket 4 to form an intermediate substrate, where the outer layer of the intermediate substrate is the steel substrate layer 1, the middle layer is the metal material layer 2, and the inner layer is the titanium alloy layer 3; Specifically, degas the jacket 4 filled with titanium alloy powder at a degassing temperature of 480 °C, evacuate to ≤8.9×10 -4 Pa and then seal the degassing nozzle; the hot isostatic pressing temperature is 760 °C, the hot isostatic pressing pressure is 155 MPa, and the hot isostatic pressing time is 4.5 h; remove the carbon steel jacket 4 by machining; Step 3. Perform differential heat treatment on the intermediate substrate. The differential heat treatment specifically includes: performing heat treatment on the steel substrate layer 1 while performing cold treatment on the titanium alloy layer 3; after the heat treatment is completed, cool the steel substrate layer 1, and keep the cold treatment on the titanium alloy layer 3 until the steel substrate layer 1 is cooled to room temperature to obtain a preform; Specifically, it includes the following processes: a. Inductively heat the steel substrate layer 1 (frequency 80 kHz), raise the temperature to 930 °C and hold for 50 min; b. Synchronously cool the titanium alloy layer 3 with compressed air (flow rate 10 m / s, temperature 30 °C) to make its temperature ≤ 500 °C; c. After the heat preservation of the steel substrate layer 1 is completed, perform spray quenching and cooling on it, and the water flow rate is 50 L / min. At this time, keep the compressed air cooling on the titanium alloy layer 3 until the steel substrate layer 1 drops to the ambient temperature; d. Perform tempering treatment on the steel substrate layer 1 at a temperature of 200 °C for 2 h by laser heat treatment (laser power is 4 kW, scanning speed is 3.5 m / min, and spot size is 2.5 mm), and then air cool after tempering; Step 4. Remove the surface oxide layer and excess amount of the preform.

[0032] In this embodiment, the shear strength at the interface between the titanium alloy and the steel is ≥ 297 MPa, the hardness of the steel is ≥ 52 HRC, and the tensile strength of the titanium alloy is ≥ 1194 MPa. The scanning electron microscope image of the titanium-steel bimetal interface prepared in this embodiment is as Figure 5 shown. It can be seen from the figure that the titanium-steel bimetal structure is dense and the connection is intact.

[0033] The interface bonding strength, steel hardness, and titanium alloy tensile strength of the titanium-steel bimetal parts prepared by this method are shown in Table 1: Table 1 Interface properties of titanium-steel bimetal parts

[0034] It can be seen from Table 1 that the interface bonding strength of the bimetal is excellent, and the high hardness of the steel and the sufficient strength of the titanium alloy are ensured through differential heat treatment.

[0035] The above are only specific embodiments of the present invention, which enable those skilled in the art to understand or implement the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention.

[0036] It should be understood that the present invention is not limited to the above-described content and can be modified and changed without departing from its scope. The scope of the present invention is only limited by the appended claims.

Claims

1. A method for preparing a powder-solid hot isostatic pressing titanium-steel bimetallic part, characterized in that, It includes the following steps: Step 1: First, preprocess the steel substrate to obtain a preform; then pre-place the metal material layer (2) on the surface of the preform to form a prefabricated steel substrate; finally, place the prefabricated steel substrate into a jacket (4), and load titanium alloy powder into the gap between the jacket (4) and the metal material layer (2); Step 2: Degas the jacket (4) loaded with titanium alloy powder, perform hot isostatic pressing on the degassed jacket (4), and remove the jacket (4) after hot isostatic pressing to form an intermediate substrate. The outer layer of the intermediate substrate is a steel substrate layer (1), the middle layer is a metal material layer (2), and the inner layer is a titanium alloy layer (3); Step 3: Perform differential heat treatment on the intermediate substrate. The differential heat treatment specifically is: while performing heat treatment on the steel substrate layer (1), perform cold treatment on the titanium alloy layer (3); after the heat treatment ends, cool the steel substrate layer (1). The cold treatment continues until the steel substrate layer (1) cools to room temperature. After the steel substrate layer (1) cools to room temperature, perform tempering treatment, and then cool to room temperature again to obtain a preform; Step 4: Remove the surface oxide layer and excess amount of the preform to obtain a titanium-steel bimetallic part.

2. The preparation method of a powder-solid hot isostatic pressing titanium-steel bimetallic part according to claim 1, characterized in that, In Step 1, the surface roughness Ra of the steel substrate is ≤ 3.2 μm.

3. The preparation method of a powder-solid hot isostatic pressing titanium-steel bimetallic part according to claim 1, characterized in that In Step 1, the material of the metal material layer (2) is one or more of copper, nickel, vanadium, and niobium, and the thickness of the metal material layer (2) is 30 μm to 180 μm.

4. The preparation method of a powder-solid hot isostatic pressing titanium-steel bimetallic part according to claim 1, characterized in that, In Step 1, the particle size of the titanium alloy powder is 15 μm to 250 μm.

5. The preparation method of a powder-solid hot isostatic pressing titanium-steel bimetallic part according to claim 1, characterized in that, In Step 2, the degassing temperature is 230°C to 480°C.

6. The preparation method of a powder-solid hot isostatic pressing titanium-steel bimetallic part according to claim 1, characterized in that, In Step 2, the temperature of the hot isostatic pressing treatment is 760°C to 910°C, the pressure of the hot isostatic pressing treatment is 110 MPa to 160 MPa, and the time of the hot isostatic pressing treatment is 1.5 h to 4.5 h.

7. The preparation method of a powder-solid hot isostatic pressing titanium-steel bimetallic part according to claim 1, characterized in that In Step 3, the heat treatment of the steel substrate layer (1) specifically is: perform induction heating or laser heat treatment on the steel substrate layer (1), the temperature of the heat treatment is 800°C to 1200°C, and the holding time is 20 min to 90 min.

8. The preparation method of a powder-solid hot isostatic pressing titanium-steel bimetallic part according to claim 1, characterized in that, In Step 3, the cold treatment of the titanium alloy layer (3) specifically is: cool the titanium alloy layer (3) with compressed air, the flow rate of the compressed air is 5 m / s to 15 m / s, and the temperature is 15°C to 45°C.

9. The preparation method of a powder-solid hot isostatic pressing titanium-steel bimetallic part according to claim 1, characterized in that, In Step 3, the temperature of the tempering treatment is 200°C to 600°C, and the time is 45 min to 4 h.

10. Application of a titanium-steel bimetallic part prepared by the preparation method according to any one of claims 1 to 9 in the preparation of rotating bodies or special-shaped parts in the fields of aerospace and marine vessels.

Images