Low-cost high-toughness particle reinforced beta titanium-based composite material plate and preparation method thereof

Abstract

The invention belongs to the technical field of metal-based composite materials, and particularly relates to a low-cost high-toughness particle reinforced beta titanium-based composite material plate and a preparation method thereof. The preparation method comprises the steps that a titanium-based composite material blank is prepared through a casting method, and the titanium-based composite material blank comprises, by weight, 3%-6% of high-purity Cr3C2 powder, 5% of high-purity aluminum particles, 5% of high-purity zirconium particles, 5% of high-purity molybdenum particles, 2%-3.6% of high-purity chromium particles and the balance 0-grade sponge titanium particles; the blank is pretreated, coated with a high-temperature anti-oxidation coating and dried, and then stepped precession type hot rolling treatment is conducted; and carrying out argon atmosphere protection annealing treatment on the semi-finished titanium-based composite material plate. The TiC / Ti-5Al-5Mo-5Zr-6Cr beta titanium-based composite material disclosed by the invention is low in cost, a prepared titanium-based composite material plate has excellent comprehensive mechanical properties, the tensile strength at room temperature is 1310MPa, the percentage elongation after fracture reaches 10.3%, and the TiC / Ti-5Al-5Mo-5Zr-6Cr beta titanium-based composite material has excellent strength and plasticity matching.

Description

Technical Field

[0001] The invention belongs to the technical field of metal-based composite materials, and in particular relates to a low-cost, high-strength and tough particle-reinforced beta-titanium-based composite material plate and a preparation method thereof. Background Art

[0002] Among the large-scale structural materials in the fields of aerospace and marine engineering, lightweight, high-strength and high-toughness β-titanium alloys have been widely used. However, some special application scenarios require titanium alloys to have both high strength and toughness and high wear resistance, and ordinary β-titanium alloys cannot meet the performance requirements. Particle-reinforced titanium-based composites have the characteristics of low density and good corrosion resistance of titanium alloys and high hardness and high wear resistance of particle-reinforced phases. Therefore, in response to the urgent demand for high-performance metal structural materials in the fields of aerospace, weapons and armaments, and marine, low-cost, high-strength and toughness particle-reinforced β-titanium-based composite materials are excellent candidate materials that meet performance indicators such as low density, high strength, high toughness, and high wear resistance.

[0003] However, the B-120VCA (Ti-13V-11Cr-3Al) widely used abroad and the TB15 (Ti-4Al-5Mo-5V-6Cr) used for aviation parts in China both contain expensive V elements, which makes the cost of titanium alloys relatively high. At the same time, due to the large differences in various indicators between the particle reinforcement phase and the titanium matrix in the titanium-based composite material, the incoordination of deformation makes the processing and forming of the titanium-based composite material very difficult, especially the preparation technology of titanium-based composite material sheets with large deformation is not mature enough. In the existing related technologies, powder metallurgy or melt casting is mainly used to prepare titanium-based composite ingots, and then hot rolling treatment is combined to prepare titanium-based composite sheets. The hot rolling process mostly uses high-temperature multi-pass rolling. The document with application number "202310724956.5" discloses "A method for synchronously improving the hardness, strength and elongation of medical degradable Zn-Li-x ternary composite sheet", which specifically involves the melting-extrusion-rolling-annealing of Zn-Li-x (x = Mg / Ag / Fe) alloy, and the components are selected according to the design composition for melting and casting to obtain an ingot; then the extruded rod is obtained by homogenization annealing and extrusion; the rod after aging heat treatment is rolled for multiple passes, and the deformation of each pass is between 10-30%, and the deformation of the nth rolling is greater than or less than the deformation of the n+1th rolling; finally, a composite sheet with a thickness of 0.1-1mm is obtained. The problems with this scheme are: the process is complex and the process cost is high, among which the deformation of each pass during rolling is small, the hot rolling process is long, the risk of hydrogen and oxygen absorption of the sheet is increased, resulting in poor matching of strength and plasticity, and the mechanical properties of the rolled sheet along the rolling direction are obviously due to other directions, and there is serious anisotropy. Summary of the invention

[0004] The present invention provides a low-cost, high-strength and tough particle-reinforced β-titanium-based composite material and a method for preparing the same, so as to solve the problems of long rolling process and high process cost in the prior art, as well as plate oxidation, poor strength-plasticity matching and severe anisotropy.

[0005] To achieve the purpose of the present invention, the technical solution adopted by the present invention is: a method for preparing a low-cost, high-strength and tough particle-reinforced β-titanium-based composite material plate, comprising the following steps:

[0006] Step 1, preparing a composite material ingot by a melt-casting method, cutting to obtain a titanium-based composite material blank, wherein the raw materials include 3-6% by weight of high-purity Cr3C2 powder, 5% by weight of high-purity aluminum AL particles, 5% by weight of high-purity zirconium ZR particles, 5% by weight of high-purity molybdenum particles, 2-3.6% by weight of high-purity chromium particles, and the remainder is grade 0 sponge titanium particles;

[0007] Step 2: grinding, alkali washing, pickling and drying the surface of the titanium-based composite material blank, coating the surface of the slab with a high-temperature anti-oxidation coating and drying it, performing a step-screw hot rolling treatment on the blank, and air-cooling the plate to room temperature after hot rolling to obtain a particle-reinforced β-titanium-based composite material plate;

[0008] Step 3: subjecting the semi-finished titanium-based composite material sheet to argon atmosphere protection annealing treatment, and after annealing treatment, grinding, alkali washing, acid washing, and drying the sheet surface to obtain a finished particle-reinforced β-titanium-based composite material sheet.

[0009] Furthermore, in the above step 2, the step-type hot rolling treatment process is as follows: the rolling temperature is 900°C, the blank is kept in a heating furnace at 900°C for 30 minutes before rolling, the rolling pressure is 300T, and the rolling speed is 2m / s; the deformation amount of the first pass is 30%, the deformation amount of the second pass is 20%, and the deformation amount of the third and fourth passes is 10%; the second, third and fourth passes are rotated 30°, 60° and 90° relative to the first pass respectively when delivering samples, and the plate is placed in a heating furnace at 900°C for 10 minutes between each pass. After the last rolling pass, the plate is air-cooled to room temperature to obtain a semi-finished titanium-based composite material plate.

[0010] Furthermore, in the above step 3, the annealing temperature is 600° C. and the temperature is kept for 2 hours.

[0011] Furthermore, in the above step 1, the melting and casting method is to use a vacuum high-frequency induction suspension melting furnace to melt the titanium-based composite material. Before melting, the inside of the melting furnace is evacuated to a vacuum degree of ≤5×10 -3Pa, and filled with high-purity argon for atmosphere protection; the induction power during smelting is 180-300kW, the smelting time is 10-30min, and after the smelting is completed, it is cooled to room temperature to obtain a titanium-based composite ingot.

[0012] Furthermore, the purity of the above-mentioned grade 0 sponge titanium is ≥99.97%, the particle size of the grade 0 sponge titanium particles is 2-10mm, the purity of the Cr3C2 powder is ≥99.95%, the particle size of the Cr3C2 powder is ≤0.325mm, the purity of the aluminum particles, zirconium particles, molybdenum particles, and chromium particles are all ≥99.99%, and the particle size is 3×3mm.

[0013] Furthermore, the above preparation method produces a low-cost, high-strength and tough particle-reinforced β-titanium-based composite material plate.

[0014] Compared with the prior art, the present invention has the following advantages:

[0015] 1. The cost of the new TiC / Ti-5Al-5Mo-5Zr-6Crβ titanium-based composite material designed by the present invention is lower than that of the commonly used titanium alloys on the market, and the cast hardness reaches 52HRC, with high hardness and good wear resistance. The element design idea of ​​the present invention is to replace the expensive V element with the Zr element, remove the Nb element, and introduce the C element in the form of Cr3C2 on the basis of the domestic M28 alloy (Ti-4Al-5Mo-5V-6Cr-1Nb) to prepare the TiC / Ti-5Al-5Mo-5Zr-6Crβ titanium-based composite material. Among them, the Al element, as a commonly used metal element in titanium alloys, can produce precipitation strengthening and improve the strength of the material; the isomorphous β-stabilizing element Mo promotes the formation and stabilization of the β phase by inhibiting the precipitation of the α phase, thereby improving the plasticity and toughness of the titanium alloy. At the same time, Mo can also refine the β phase grains and improve the alloy's deformation resistance through the solute atom effect and solid solution strengthening mechanism; the main function of Cr is to improve the strength of titanium alloy by forming a eutectic structure with a specific composition and structure. It also uses the difference in the diffusion rate of Cr and Al at high temperatures to form Al-rich and Cr-poor nanodomains in each β grain. These nanodomains promote the nucleation of martensite during the cooling process. The existence of the chemical interface limits the rapid growth of martensite and further refines the grains. At the same time, Cr is the metal with the highest hardness. The addition of Cr will significantly improve the hardness and wear resistance of the material; the C element in Cr3C2 will react in situ to generate TiC during the material smelting process, further improving the mechanical properties of the composite material.

[0016] 2. The present invention proposes a "step-screw-in" hot rolling technology for the rolling of titanium-based composite material plates, where "step" refers to the gradient change of deformation. In the early stage of rolling, the internal dislocation density of the material is low, which is suitable for single-pass large deformation rolling. After two passes of rolling, the dislocation density increases. Reducing the deformation can reduce the risk of plate cracking. The so-called "screw-in" refers to the angle at which the blank enters the rollers changes with the pass. The addition of this invention point can make the titanium-based composite material slab quickly reach the expected deformation after only 4 hot rolling processes, shorten the hot rolling process, and avoid the plate oxidation problem caused by multiple hot rolling processes. The present invention can effectively reduce anisotropy through the "step-screw-in hot rolling" hot rolling technology, so that the mechanical properties in all directions on the RD-TD plane are at the same level, effectively regulate the distribution morphology of the reinforcement phase in the titanium-based composite material plate, and achieve uniform distribution of the reinforcement phase.

[0017] 3. The titanium-based composite material sheet prepared by the present invention is annealed under the protection of argon atmosphere to further reduce the risk of hydrogen and oxygen absorption, and a particle-reinforced β-titanium-based composite material with micro-nano multi-scale α-phase hybrid reinforcement can be obtained. The prepared titanium-based composite material sheet has excellent comprehensive mechanical properties, a room temperature tensile strength of 1310MPa, an elongation after fracture of 10.3%, and has excellent strength-plasticity matching. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is the macroscopic morphology of the low-cost, high-strength and tough particle-reinforced β-titanium-based composite material plate of Example 1 of the present invention.

[0019] Figure 2 This is the microstructure of the low-cost, high-strength and tough particle-reinforced β-titanium-based composite material plate of Example 1 of the present invention.

[0020] Figure 3 This is a micro-nano multi-scale α phase SEM photograph of the low-cost, high-strength and tough particle-reinforced β-titanium-based composite material plate of Example 1 of the present invention.

[0021] Figure 4 The room temperature tensile properties of the low-cost, high-strength and tough particle-reinforced β-titanium-based composite material plate material of Example 1 of the present invention. DETAILED DESCRIPTION

[0022] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments.

[0023] Example 1, a method for preparing a low-cost, high-performance particle-reinforced β-titanium-based composite material plate, comprising the following steps:

[0024] Step 1. Weigh the raw material package containing the above raw materials by mass fraction, the raw materials comprising 6% of high-purity Cr3C2 powder, 5% of high-purity aluminum particles, 5% of high-purity zirconium particles, 5% of high-purity molybdenum particles, 0.8% of high-purity chromium particles, and the remainder is grade 0 sponge titanium particles; the purity of the grade 0 sponge titanium is ≥99.97%, and the particle size of the grade 0 sponge titanium particles is 2-10mm, the purity of the Cr3C2 powder is ≥99.95%, and the particle size of the Cr3C2 powder is 0.325mm; the purity of the aluminum particles, zirconium particles, molybdenum particles, and chromium particles are all ≥99.99%, and the particle size is 3×3mm.

[0025] A vacuum induction suspension melting furnace is used to melt the titanium-based composite material. Before the vacuum induction suspension melting, the inside of the melting furnace is evacuated to a vacuum degree of 5×10-3Pa, and argon gas is filled in for atmosphere protection. The induction power supply power during the vacuum induction suspension melting is 280kW, and the melting time is 20min. After the melting is completed, the furnace is cooled to room temperature to obtain a titanium-based composite ingot, and the ingot is cut to obtain a 15mm thick titanium-based composite blank.

[0026] Step 2: Grind, alkali-wash, pickle and air-dry the surface of the titanium-based composite material slab in step 1, apply a high-temperature anti-oxidation coating on the surface of the slab and dry it; place the titanium-based composite material slab in a 900°C heating furnace for 30 minutes, and then perform step-screw hot rolling on the rolling mill. In this embodiment, the step-screw hot rolling pressure is 300T, the rolling speed is 2m / s, the deformation of the first pass is 30%, the deformation of the second pass is 20%, and the deformation of the third and fourth passes is 10%. The second, third and fourth passes of sample delivery are rotated counterclockwise by 30°, 60° and 90° relative to the first pass, respectively. Place the plate in a 900°C heating furnace for 10 minutes between each rolling pass. After the last rolling, air-cool the plate to room temperature to obtain a semi-finished titanium-based composite material plate with a total rolling deformation of approximately 70%;

[0027] Step 3: Place the semi-finished titanium-based composite material plate in a heating furnace at 600°C for 2 hours for annealing, then air-cool to room temperature. After annealing, grind, alkali-wash, acid-wash, and dry the surface of the titanium-based composite material plate to obtain a finished titanium-based composite material plate with a thickness of about 4.5 mm.

[0028] from Figure 1 It can be seen that the low-cost, high-strength and tough particle-reinforced β-titanium-based composite material plate prepared in Example 1 of the present invention has a good appearance without defects.

[0029] from Figure 2 It can be seen that the reinforcement phase is evenly distributed in the low-cost, high-strength and tough particle-reinforced β-titanium-based composite material plate prepared in Example 1 of the present invention.

[0030] from Figure 3 It can be seen that the low-cost, high-strength and tough particle-reinforced β-titanium-based composite material prepared in Example 1 of the present invention has a micro / nano multi-scale α phase, and the hierarchical multi-scale structure brings better mechanical properties and obtains excellent tensile strength and elongation.

[0031] from Figure 4 It can be seen that the low-cost, high-strength and tough particle-reinforced β-titanium-based composite material plate prepared in Example 1 of the present invention has good room-temperature tensile properties, a room-temperature tensile strength of 1310 MPa, and an elongation after fracture of 10.3%, and has good strength-plasticity matching.

[0032] The above is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent change made to the above embodiment according to the technical essence of the invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A method for preparing a low-cost, high-strength and tough particle-reinforced β-titanium-based composite material plate, characterized in that: The following steps are involved: Step 1, preparing a composite material ingot by a melt-casting method, cutting to obtain a titanium-based composite material blank, wherein the raw materials include 3-6% by weight of high-purity Cr3C2 powder, 5% by weight of high-purity aluminum AL particles, 5% by weight of high-purity zirconium ZR particles, 5% by weight of high-purity molybdenum particles, 2-3.6% by weight of high-purity chromium particles, and the remainder is grade 0 sponge titanium particles; Step 2: grinding, alkali washing, pickling and drying the surface of the titanium-based composite material blank, coating the surface of the slab with a high-temperature anti-oxidation coating and drying it, performing a step-screw hot rolling treatment on the blank, and air-cooling the plate to room temperature after hot rolling to obtain a particle-reinforced β-titanium-based composite material plate; Step 3: subjecting the semi-finished titanium-based composite material sheet to argon atmosphere protection annealing treatment, and after annealing treatment, grinding, alkali washing, acid washing, and drying the sheet surface to obtain a finished particle-reinforced β-titanium-based composite material sheet.

2. The method for preparing a low-cost, high-strength and tough particle-reinforced β-titanium-based composite material sheet according to claim 1, characterized in that: In the step 2, the step-screw hot rolling treatment process is as follows: the rolling temperature is 900°C, the blank is kept warm in a heating furnace at 900°C for 30 minutes before rolling, the rolling pressure is 300T, and the rolling speed is 2m / s; the deformation amount of the first pass is 30%, the deformation amount of the second pass is 20%, and the deformation amount of the third and fourth passes is 10%; when the second, third and fourth passes are sampled, they are rotated 30°, 60° and 90° relative to the first pass respectively, and the plate is placed in a heating furnace at 900°C for 10 minutes between each pass. After the last rolling pass, the plate is air-cooled to room temperature to obtain a semi-finished titanium-based composite material plate.

3. The method for preparing a low-cost, high-strength and tough particle-reinforced β-titanium-based composite material sheet according to claim 2, characterized in that: The annealing treatment in step 3 is carried out at a temperature of 600° C. for 2 hours.

4. A method for preparing a low-cost, high-strength and tough particle-reinforced β-titanium-based composite material sheet according to any one of claims 1 to 3, characterized in that: In the step 1, the melting and casting method is to use a vacuum high-frequency induction suspension melting furnace to melt the titanium-based composite material. Before melting, the inside of the melting furnace is evacuated to a vacuum degree of ≤5×10 -3 Pa, and filled with high-purity argon for atmosphere protection; the induction power during smelting is 180-300kW, the smelting time is 10-30min, and after the smelting is completed, it is cooled to room temperature to obtain a titanium-based composite ingot.

5. The method for preparing a low-cost, high-strength and tough particle-reinforced β-titanium-based composite material sheet according to claim 4, characterized in that: The purity of the grade 0 titanium sponge is ≥99.97%, the particle size of the grade 0 titanium sponge particles is 2-10mm, the purity of the Cr3C2 powder is ≥99.95%, the particle size of the Cr3C2 powder is ≤0.325mm, the purity of the aluminum particles, zirconium particles, molybdenum particles, and chromium particles are all ≥99.99%, and the particle size is 3×3mm.

6. A low-cost, high-strength and tough particle-reinforced β-titanium-based composite material plate prepared by the preparation method according to claim 1.

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