A mixed deoxidizer and its application in HDH

Abstract

The present invention discloses a mixed deoxidizer and its application in HDH, belonging to the technical field of inorganic deoxidizers. The components of the mixed deoxidizer are selected from at least three of borides, carbides, hydrides and titanium dichloride, and the deoxidation method is: the mixed deoxidizer and titanium hydride are mixed and kept at 400-850°C for 1-24h; the amount of the mixed deoxidizer does not exceed 0.1% of the mass of high-oxygen titanium hydride. The mixed deoxidizer of the present invention and its application method in HDH can solve the problems of high oxygen content of titanium hydride, powder agglomeration, poor mechanical properties of related molded products, etc., and improve the actual industrial application value of titanium hydride and its processed products.

Description

Technical Field

[0001] The invention belongs to the technical field of inorganic deoxidizers, and in particular relates to a mixed deoxidizer and application thereof in HDH. Background Art

[0002] (Saturated or unsaturated) titanium hydride powder, titanium powder and titanium alloy powder are important raw materials in the titanium material processing process. They have been used in many fields such as aerospace, biomedicine, weapons and equipment, petrochemicals, etc. At present, the use of titanium hydride powder dehydrogenation has become one of the important methods for preparing titanium powder and titanium alloy powder. Titanium hydride dehydrogenation (Hydrogenation-Dehydrogenation, HDH) is to treat the titanium raw material with hydrogen absorption at a certain temperature and hydrogen pressure to form titanium hydride powder, and then dehydrogenate it at high temperature to finally obtain dehydrogenated titanium powder; this method has simple process, easy to obtain raw materials, relatively low cost, and can be mass-produced. However, the unsaturated titanium hydride or hydrogenated dehydrogenated titanium powder products produced by HDH have high oxygen and nitrogen content, poor sintering performance, and are prone to tissue coarsening during the sintering process, which seriously restricts its subsequent application.

[0003] The purity of commercially available titanium hydride powder is basically above 98%, and the oxygen content is basically below 0.5%. The higher the purity of titanium hydride, the higher the price. In order to respond to the development trend of waste resource utilization and effectively reduce production costs, some researchers have recycled various titanium-containing waste materials such as sponge titanium waste, titanium alloy coarse materials, titanium-containing processing debris, etc. to prepare (saturated or unsaturated) titanium hydride. However, the (saturated or unsaturated) titanium hydride prepared in this case has too high an impurity content, which makes the above problems it faces more serious and basically cannot be directly put into industrial applications.

[0004] Chinese patent CN116477568A completes the dehydrogenation and deoxygenation process of the hydrogenated metal powder by continuously heating and keeping the temperature under high temperature stirring. Although the dehydrogenation degree is good, this method cannot effectively reduce the oxygen content in the product, and is not suitable for the deoxygenation process of high-oxygen-content titanium hydride processed from waste materials. Summary of the invention

[0005] The purpose of the present invention is to provide a mixed deoxidizer and its application in HDH, so as to solve the problems of high oxygen content, powder agglomeration, poor mechanical properties of products caused by incomplete deoxidation of titanium hydride powder during the HDH process, and to improve the actual industrial application value of titanium hydride and its processed products.

[0006] First, the present invention provides a mixed deoxidizer, the components of which are selected from at least three of borides, carbides, hydrides and titanium dichloride; the boride includes at least one of CaB6, LaB6, and NbB6, the carbide includes CaC2, and the hydride includes at least one of LaH2, YH2, and CaH2.

[0007] It is impossible to remove oxygen from high-oxygen-content titanium hydride powder to the maximum extent by using only a single component. The oxygen content in the product is much higher than the oxygen content level of commercially available hydrogenated dehydrogenated titanium powder. Therefore, a more efficient deoxidation component is required to treat the material.

[0008] In one embodiment, the components of the mixed deoxidizer include boride, hydride and titanium dichloride.

[0009] All of the above substances can be used as efficient deoxidation catalysts. Borides such as CaB6 can promote the solid solution of active hydrogen in titanium hydride during the HDH process, and help active hydrogen react with oxygen impurities to form products such as water and ammonia. However, the catalytic deoxidation degree of borides is limited, and the oxygen can only be completely removed by heating to above 1100°C. However, the grains of titanium hydride processed products at this temperature will grow excessively or the structure will be destroyed. Therefore, the deoxidation effect of using only borides in this application is not ideal. After a large number of experiments, it was found that TiCl2 with high activity can also promote the degree of oxygen removal by active H in titanium hydride. It is speculated that TiCl2 will produce some active Ti and unsaturated TiH at high temperatures, which will catalyze the formation of active H and promote the removal of oxygen by H. The product using TiCl2 escapes in the form of gas at high temperatures, and will not cause the second phase in the processed product to hinder its mechanical properties. In addition to having high reducibility, hydrides such as CaH2 may also serve as a source of active H under high temperature conditions, promoting the removal of oxygen in titanium hydride powder, and its addition can also refine the grains of titanium hydride and improve the strength and ductility of processed products. The present invention uses a very small amount of boride, hydride and titanium dichloride in combination to show the maximum catalytic effect to reduce the oxygen content in titanium hydride processed products. It is worth noting that the relative content of the above substances must be strictly controlled in the technology to achieve the best deoxygenation effect. Although the use of borides can also improve the mechanical strength of dehydrogenated titanium powder processed products such as tensile strength and hardness, excessive use will have an adverse effect on the fatigue performance of the latter; in addition, excessive TiCl2 may also introduce new impurities into the product, which is not conducive to the performance of titanium hydride processed products.

[0010] Furthermore, the mass ratio of the boride, hydride and titanium dichloride is 1-4:1-2:1.

[0011] In one embodiment, the components of the mixed deoxidizer include hydride, carbide and titanium dichloride.

[0012] Furthermore, the mass ratio of the hydride, carbide and titanium dichloride is 2-3:2-4:1.

[0013] Preferably, the boride is CaB6; the carbide is CaC2; and the hydride is CaH2.

[0014] Furthermore, the present invention also provides the use of the mixed deoxidizer in HDH, specifically: mixing the mixed deoxidizer and titanium hydride, and keeping the mixture at 400-850° C. for 1-24 hours; the amount of the mixed deoxidizer does not exceed 0.1% of the mass of titanium hydride.

[0015] Furthermore, the D90 of the mixed deoxidizer is less than 1 μm and is not 0. The particle size of the components of the mixed deoxidizer is adjusted to make it easy to combine with the titanium hydride powder, increase the reaction area, and adhere to the surface of the titanium hydride powder to prevent the sintering of titanium hydride during deoxidation, and the dosage of the two can be effectively reduced to minimize interference with the molding of processed products after titanium hydride dehydrogenation and deoxidation.

[0016] Further, the D50 of the titanium hydride is ≤200μm and is not 0; preferably 0.5-200μm, and options include but are not limited to 0.5μm, 1μm, 5μm, 10μm, 15μm, 25μm, 35μm, 50μm, 70μm, 100μm, 120μm, 150μm, 160μm, 170μm, 180μm, 190μm, 200μm, etc.

[0017] Furthermore, D50 of the mixture obtained by mixing the mixed deoxidizer and titanium hydride is ≤25μm and is not 0; preferably 0.01-25μm, and options include but are not limited to 0.01μm, 0.05μm, 0.1μm, 0.4μm, 1.0μm, 2.0μm, 3.0μm, 4.0μm, 5.0μm, 8.0μm, 9.0μm, 10μm, 13μm, 15μm, 17μm, 20μm, 22μm, 25μm, etc.

[0018] Furthermore, the method of mixing the mixed deoxidizer and titanium hydride is ball milling.

[0019] Furthermore, the ball-to-material ratio of the ball milling process is 3-15:1, the rotation speed is 200-800r / min, and the ball milling time is 2-24h.

[0020] Furthermore, the application of the mixed deoxidizer in HDH is specifically as follows: the mixed deoxidizer and titanium hydride are mixed and ball-milled and kept at 400-600°C for 1-8h, 650-800°C for 1-6h, 820°C-850°C for 1-8h, and then cooled.

[0021] Furthermore, in the method, after the moisture of the mixed deoxidizer and titanium hydride mixture is vacuum dried, the mixture is kept at 500-550°C for 3-4 hours, 700-750°C for 2-3 hours, and then the temperature is increased to 820°C-850°C and kept for 2-5 hours.

[0022] The use of mixed deoxidizers to remove oxygen impurities from titanium hydride in the HDH process involves multiple phase change steps, such as TiH2→TiH1.5 (unsaturated titanium hydride)→Ti (solid solution)→Ti. Each step has its own specific temperature range and reaction kinetics; in this process, hydrogen atoms can remove part of the oxygen from the surface oxide film and have the effect of cleaning the surface; by precisely controlling the heating temperature, the degree and rate of the dehydrogenation reaction of the TiH powder can be controlled to increase the removal of oxygen, and the damage to the material structure caused by too fast a reaction can be reduced. At the appropriate temperature, the product grain refinement and grain growth uniformity can be promoted, the uniformity of the product particle size distribution can be improved, the reaction activity and powder fluidity can be enhanced, and the contradictions in the technology can be solved (increasing the ball milling speed and time is an effective way to improve the uniformity of the particle size distribution, but the oxygen content of titanium hydride and the product in this process increases significantly).

[0023] Furthermore, the oxygen content of the titanium hydride is 0.15-0.6%.

[0024] Furthermore, the titanium hydride is processed from Ti-containing waste and / or is commercially available common titanium hydride.

[0025] In one embodiment, the method for preparing titanium hydride comprises: heating Ti-containing waste to 500-600° C. under vacuum, introducing high-purity hydrogen, maintaining the pressure in the device at 0.05-0.09 MPa, and performing hydrogenation treatment for 2-8 hours.

[0026] Furthermore, the Ti-containing waste includes but is not limited to at least one of waste titanium sponge, coarse titanium and titanium alloy powder, titanium and titanium alloy chips, and unsaturated titanium hydride waste.

[0027] Furthermore, the oxygen content of the product obtained after deoxygenation according to the method is ≤2000ppm.

[0028] The product hydrogenated dehydrogenated titanium powder prepared after the mixed deoxidizer of the present application is applied to the HDH process can be used in industrial production such as the preparation of titanium alloy powder, and the titanium alloy powder includes but is not limited to any one or more of TA7, TA11, TA12, TA19, TA15, Ti53311S, TC4, TC6, TC11, TC16, TC17, TC21, TC18, and TC19.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] (1) The mixed deoxidizer of the present invention uses at least three of boride, hydride, carbide and TiCl2 in combination, which can reduce the oxygen content in the dehydrogenated titanium powder to below 2000ppm (i.e. 0.2%), which can solve the problem that TiH powder and its processed products have high oxygen content and poor mechanical properties of the molded products and cannot be industrially applied. The deoxidation method is simple and easy to operate, which can effectively reduce the production cost of related processed products.

[0031] (2) The condition parameters for controlling the use of the mixed deoxidizer in HDH according to the present invention can effectively reduce the oxygen content of the titanium hydride powder processed products, refine the grains of the processed products, improve the uniformity of the particle size distribution, and thus improve the mechanical properties of the related molded products;

[0032] (3) The present invention controls the in-situ grinding of titanium hydride and mixed deoxidizer during the HDH process, so that the two can be mixed more evenly. The adhesion of the nano-scale mixed deoxidizer on the surface of the titanium hydride powder can isolate the titanium hydride, avoid sintering during the deoxidation process, and also prevent further oxidation, and has a certain grinding aid effect;

[0033] (4) The product obtained by the HDH process using a mixed deoxidizer in the present invention has a low oxygen content, a uniform particle size distribution, and contains an appropriate amount of reinforcing phase. It can be used in titanium alloy products to exhibit excellent mechanical properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 : Morphology of the product obtained by the HDH process using the mixed deoxidizer of Example 1.

[0035] Figure 2 : Morphology of the product obtained by the HDH process using the mixed deoxidizer of Example 2.

[0036] Figure 3 : Morphology of the product obtained by the HDH process using the mixed deoxidizer of Example 3.

[0037] Figure 4 : Morphology of the product obtained by the HDH process of Comparative Example 2.

[0038] Figure 5: Morphology of the product obtained by the HDH process of Comparative Example 5. DETAILED DESCRIPTION

[0039] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the 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.

[0040] Unless otherwise specified, in the following embodiments and comparative examples, the titanium hydride is prepared from titanium scraps containing Ti waste, and the preparation method is as follows: the titanium scraps are placed in a reaction device under vacuum and argon is passed through to protect the system so that the pressure of the system is maintained at 0.02 MPa; the reaction device is heated to a chamber temperature of 550°C and then high-purity hydrogen is passed through to maintain the pressure in the device at 0.07 MPa. After hydrogenation treatment for 6 hours, the reaction device is naturally cooled to obtain titanium hydride with a D50 of 180 μm and an oxygen content of 0.51%.

[0041] TiCl2 has a D90 of 0.87 μm and was purchased from Hubei Youren New Materials Co., Ltd. CaB6 has a D90 of 0.93 μm, CaH2 has a D90 of 0.89 μm, LaB6 has a D90 of 0.50 μm, and YH2 has a D90 of 0.72 μm, all of which were purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.

[0042] Example 1

[0043] This embodiment provides a mixed deoxidizer, the components of which are CaB6, CaH2 and TiCl2, and the mass ratio of the three is 2:1:1.

[0044] This embodiment also provides the application of the mixed deoxidizer in HDH, specifically:

[0045] (1) Titanium hydride and mixed deoxidizer were mixed by ball milling, the ball-to-material ratio of the ball milling process was 5:1, the rotation speed was 600 r / min, and the ball milling time was 12 h;

[0046] The dosage of the mixed deoxidizer is 0.06% of the mass of titanium hydride; the D50 of the mixed powder of titanium hydride and the mixed deoxidizer after ball milling is 15 μm.

[0047] (2) The mixed powder is placed in a vacuum dehydrogenation device (which has been vacuum treated with Ar gas) and the reaction chamber of the device is evacuated to 1×10 -3 Pa, slowly raise the temperature to 200℃, keep warm for 1h and dry the mixed powder.

[0048] (3) After drying, the temperature of the reaction chamber is raised to 550°C and kept for 4 hours, then raised to 750°C and kept for 3 hours, and then raised to 830°C and kept for 3 hours. After the insulation is completed, the temperature of the reaction chamber is lowered to room temperature to obtain the product hydrogenated dehydrogenated titanium powder.

[0049] Example 2

[0050] This embodiment provides a mixed deoxidizer, the components of which are CaB6, CaH2 and TiCl2, and the mass ratio of the three is 1:2:1.

[0051] This embodiment also provides the application of the mixed deoxidizer in HDH, specifically:

[0052] (1) Titanium hydride and mixed deoxidizer were mixed by ball milling, the ball-to-material ratio of the ball milling process was 15:1, the rotation speed was 800 r / min, and the ball milling time was 4 h;

[0053] The dosage of the mixed deoxidizer is 0.1% of the mass of titanium hydride, and the D50 of the mixed powder of titanium hydride and the mixed deoxidizer after ball milling is 3 μm.

[0054] (2) The mixed powder is placed in a vacuum dehydrogenation device (which has been vacuum treated with Ar gas) and the reaction chamber of the device is evacuated to 1×10 -3 Pa, slowly raise the temperature to 200℃, keep it for 2h and dry the mixed powder.

[0055] (3) After drying, the temperature of the reaction chamber is raised to 600°C and kept at this temperature for 2 hours, then the temperature is further raised to 800°C and kept at this temperature for 5 hours, and then the temperature is raised to 850°C and kept at this temperature for 2 hours. After the temperature is maintained at this temperature, the temperature of the reaction chamber is lowered to room temperature to obtain the product hydrogenated dehydrogenated titanium powder.

[0056] Example 3

[0057] This embodiment provides a mixed deoxidizer, the components of which are CaB6, CaH2 and TiCl2, and the mass ratio of the three is 4:1:1.

[0058] This embodiment also provides the application of the mixed deoxidizer in HDH, specifically:

[0059] Titanium hydride and mixed deoxidizer were mixed by ball milling, the ball-to-material ratio was 3:1, the rotation speed was 200 r / min, and the ball milling time was 24 h.

[0060] The dosage of the mixed deoxidizer is 0.02% of the mass of titanium hydride; the D50 of the mixed powder of titanium hydride and the mixed deoxidizer after ball milling is 25 μm;

[0061] (2) The mixed powder is placed in a vacuum dehydrogenation device (which has been vacuum treated with Ar gas) and the reaction chamber of the device is evacuated to 1×10 -3Pa, slowly raise the temperature to 200℃, keep warm for 1h and dry the mixed powder.

[0062] (3) After drying, the temperature of the reaction chamber is raised to 400°C and kept for 8 hours, then raised to 650°C and kept for 6 hours, and then raised to 820°C and kept for 3 hours. After the insulation is completed, the temperature of the reaction chamber is lowered to room temperature to obtain the product hydrogenated dehydrogenated titanium powder.

[0063] Example 4

[0064] This embodiment provides a mixed deoxidizer, the components of which are CaH2, CaC2 and TiCl2, and the mass ratio of the three is 2:3:1.

[0065] This embodiment also provides the application of the mixed deoxidizer in HDH, specifically:

[0066] (1) Titanium hydride and mixed deoxidizer were mixed by ball milling, the ball-to-material ratio of the ball milling process was 5:1, the rotation speed was 500 r / min, and the ball milling time was 14 h;

[0067] The dosage of the mixed deoxidizer is 0.06% of the mass of titanium hydride; the D50 of the mixed powder of titanium hydride and the mixed deoxidizer after ball milling is 17.6 μm.

[0068] (2) The mixed powder is placed in a vacuum dehydrogenation device (which has been vacuum treated with Ar gas) and the reaction chamber of the device is evacuated to 1×10 -3 Pa, slowly raise the temperature to 200℃, keep warm for 1h and dry the mixed powder.

[0069] (3) After drying, the temperature of the reaction chamber is raised to 500°C and kept for 6 hours, then raised to 700°C and kept for 3 hours, and then raised to 850°C and kept for 11 hours. After the insulation is completed, the temperature of the reaction chamber is lowered to room temperature to obtain the product hydrogenated dehydrogenated titanium powder.

[0070] Example 5

[0071] This embodiment provides a mixed deoxidizer, the components of which are YH2, LaB6 and TiCl2, and the mass ratio of the three is 2:1:1.

[0072] This embodiment also provides the application of the mixed deoxidizer in HDH, specifically:

[0073] (1) Titanium hydride and mixed deoxidizer were mixed by ball milling, the ball-to-material ratio of the ball milling process was 15:1, the rotation speed was 800 r / min, and the ball milling time was 4 h;

[0074] The dosage of the mixed deoxidizer is 0.1% of the mass of titanium hydride; the D50 of the mixed powder of titanium hydride and the mixed deoxidizer after ball milling is 3.7 μm.

[0075] (2) The mixed powder is placed in a vacuum dehydrogenation device (which has been vacuum treated with Ar gas) and the reaction chamber of the device is evacuated to 1×10 -3 Pa, slowly raise the temperature to 200℃, keep it for 2h and dry the mixed powder.

[0076] (3) After drying, the temperature of the reaction chamber is raised to 600°C and kept at this temperature for 2 hours, then the temperature is further raised to 800°C and kept at this temperature for 5 hours, and then the temperature is raised to 850°C and kept at this temperature for 2 hours. After the temperature is maintained at this temperature, the temperature of the reaction chamber is lowered to room temperature to obtain the product hydrogenated dehydrogenated titanium powder.

[0077] Example 6

[0078] This embodiment provides a mixed deoxidizer, the components of which are LaH2, LaB6 and TiCl2, and the mass ratio of the three is 1:4:1.

[0079] This embodiment also provides the application of the mixed deoxidizer in HDH, specifically:

[0080] (1) Titanium hydride and mixed deoxidizer were mixed by ball milling, the ball-to-material ratio was 3:1, the rotation speed was 200 r / min, and the ball milling time was 24 h;

[0081] The dosage of the mixed deoxidizer is 0.02% of the mass of titanium hydride; the D50 of the mixed powder of titanium hydride and the mixed deoxidizer after ball milling is 25 μm.

[0082] (2) The mixed powder is placed in a vacuum dehydrogenation device (which has been vacuum treated with Ar gas) and the reaction chamber of the device is evacuated to 1×10 -3 Pa, slowly raise the temperature to 200℃, keep warm for 1h and dry the mixed powder.

[0083] (3) After drying, the temperature of the reaction chamber is raised to 400°C and kept for 8 hours, then raised to 650°C and kept for 6 hours, and then raised to 820°C and kept for 3 hours. After the insulation is completed, the temperature of the reaction chamber is lowered to room temperature to obtain the product hydrogenated dehydrogenated titanium powder.

[0084] Comparative Example 1

[0085] This comparative example provides a mixed deoxidizer and its application in HDH.

[0086] The mixed deoxidizer is consistent with that in Example 1.

[0087] The difference between the application of the mixed deoxidizer in HDH and Example 1 is that step (3) is: after drying, the reaction chamber is heated to 300°C and kept warm for 3 hours, 600°C and kept warm for 6 hours, and then heated to 900°C and kept warm for 4 hours. After the insulation is completed, the reaction chamber temperature is lowered to room temperature to obtain the product hydrogenated dehydrogenated titanium powder.

[0088] Comparative Example 2

[0089] This comparative example provides a mixed deoxidizer and its application in HDH.

[0090] The mixed deoxidizer is consistent with that in Example 1.

[0091] The difference between the application of the mixed deoxidizer in HDH and that in Example 1 is that the amount of the mixed deoxidizer used is 0.3% of the mass of the titanium hydride powder.

[0092] Comparative Example 3

[0093] This comparative example provides a mixed deoxidizer and its application in HDH.

[0094] The mixed deoxidizer comprises CaB6 and TiCl2, and the mass ratio of the two is 1:3.

[0095] The difference between the application of the mixed deoxidizer in HDH and Example 1 is that the mixed deoxidizer used is the mixed deoxidizer of this comparative example.

[0096] Comparative Example 4

[0097] This comparative example provides a mixed deoxidizer and its application in HDH.

[0098] The mixed deoxidizer comprises CaH2, CaB6 and TiCl2, and the mass ratio of the two is 3:1:2.

[0099] The difference between the application of the mixed deoxidizer in HDH and Example 1 is that the mixed deoxidizer used is the mixed deoxidizer of this comparative example.

[0100] Comparative Example 5

[0101] This comparative example provides a HDH method for titanium hydride, specifically:

[0102] (1) Titanium hydride was milled by ball milling. The ball-to-material ratio was 5:1, the rotation speed was 600 r / min, and the ball milling time was 12 h. The D50 of the titanium hydride powder after ball milling was 21 μm.

[0103] (2) The milled titanium hydride powder is placed in a vacuum dehydrogenation device (which has been vacuum treated with Ar gas), and the reaction chamber of the device is evacuated to 1×10 -3 Pa, slowly raise the temperature to 200℃, keep warm for 1h to dry the powder.

[0104] (3) After drying, the temperature of the reaction chamber is raised to 800°C and kept at this temperature for 10 hours. After the insulation is completed, the temperature of the reaction chamber is lowered to room temperature to obtain the product hydrogenated dehydrogenated titanium powder.

[0105] Comparative Example 6

[0106] This comparative example provides a mixed deoxidizer and its application in HDH.

[0107] The mixed deoxidizer is consistent with that in Example 1;

[0108] The difference between the application of the mixed deoxidizer in HDH and Example 1 is that the titanium hydride used is prepared by the following method: a high-oxygen titanium raw material is placed in a reaction device under vacuum and argon is passed through to protect the system so that the pressure of the system is maintained at 0.02 MPa; the reaction device is heated to a chamber temperature of 450°C and then high-purity hydrogen is passed through to maintain the pressure in the device at 0.07 MPa. After hydrogenation treatment for 8 hours, it is naturally cooled to room temperature to obtain a hydrogenated crude product; a titanium hydride powder having an average particle size D50 of 65 μm and an oxygen content of 0.84%.

[0109] Performance testing method:

[0110] 1. Use nitrogen and oxygen analyzer to detect the oxygen and hydrogen content of the product;

[0111] 2. Tensile strength and elongation: The products prepared in the above embodiments and comparative examples were respectively used and processed into titanium products of the same scale by injection molding process, and the products were tested in accordance with the provisions of GB / T 220-2010 Tensile test method for metal materials.

[0112] The injection molding process is as follows: (1) Mix hydrogenated dehydrogenated titanium metal powder and a binder (mixed by polymethacrylate and polyethylene glycol in a mass ratio of 1:1, with a solid content of 60%) in a mass ratio of 3:2, knead at 150°C for 2 hours, then cool and crush into feed particles; (2) Add the feed particles to the injection molding machine, heat to 170°C, and squeeze them into the mold cavity. After filling, cool for a period of time to obtain a green body; (3) Place the green body in a 200°C debinding furnace for high-temperature debinding for 5 hours; (4) Place the part in a vacuum furnace for high-temperature sintering for 5 hours at a sintering temperature of 1200°C, and then naturally cool to room temperature.

[0113] The performance test results are shown in Table 1.

[0114] Table 1

[0115]

[0116] Summarize:

[0117] As can be seen from the above table, the products prepared by the HDH process using the mixed deoxidizers of Examples 1-6 have very low oxygen contents. Figure 1-3 It can be seen that the HDH products prepared in Examples 1-3 have higher and finer grain regularity, more uniform particle size distribution, and the processed titanium alloy products also show excellent tensile strength and elongation.

[0118] By comparing Examples 1-4 and Comparative Example 1, it can be seen that if the temperature is too high during the dehydrogenation and deoxidation process, it may cause sintering, grain coarsening and structural damage of titanium hydride and its processed products, while if the temperature is too low, it is impossible to achieve suitable deoxidation conditions; only by controlling the insulation temperature to adapt it to different reaction kinetics processes can the titanium hydride powder be deoxidized and dehydrogenated at an optimal rate, and while efficiently completing the deoxidation, a finer and more uniform product grain size can be obtained, thereby enhancing the mechanical properties of the deoxidized product, i.e., the hydrogenated dehydrogenated titanium powder molded product.

[0119] Comparison of Examples 1-4 and Comparative Examples 2-4 shows that the deoxidation effect of titanium hydride powder is the best when CaH2, CaB6 and TiCl2 are used as mixed deoxidizer components. Figure 4 This is the morphology of the hydrogenated dehydrogenated titanium powder prepared by the HDH method of Comparative Example 2. It can be seen that when the amount of the mixed deoxidizer is too much, it does not have a significant adverse effect on the particle morphology of the product, and even the particle size is reduced, but the deoxidation effect does not show an ideal improvement. According to the mechanical properties of the molded product, it is speculated that a new impurity phase may be introduced into the system at this time, resulting in a more obvious reduction in the mechanical properties of the product than the enhancement of the mechanical properties by grain refinement. Therefore, it is necessary to strictly control the amount and component ratio of the mixed deoxidizer.

[0120] Comparative Example 5 is a process of simply performing hydrogenation, dehydrogenation and deoxygenation in the industry. According to the results, when no mixed deoxidizer is used and no targeted temperature control is performed, the oxygen content in the product increases as expected and the degree of reduction in hydrogen content does not meet the requirements; at the same time, according to the attached Figure 5 It can be seen that the hydrogenated dehydrogenated titanium powder prepared by the HDH method without adding a mixed deoxidizer still has obvious problems of particle agglomeration and uneven size. It is worth noting that the comparison of the particle size of the titanium hydride powder in step (1) of Examples 1-4 and Comparative Example 5 further confirms that the mixed deoxidizer also has the effect of refining the particle size of the titanium hydride powder during the in-situ grinding process, which is beneficial to the subsequent deoxidation and dehydrogenation operations.

[0121] Comparative Example 6 uses high-oxygen hydride titanium with an oxygen content of 0.84%. According to its test data, when the oxygen content of the raw material is too high to exceed the specified value, even the HDH process using a mixed deoxidizer in this application cannot effectively reduce the oxygen content in the hydrogenated dehydrogenated titanium powder.

[0122] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0123] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. Application of a mixed deoxidizer in HDH, characterized in that: The application is specifically as follows: the mixed deoxidizer and titanium hydride are mixed and ball-milled and kept at 400-600°C for 1-8h, 650-800°C for 1-6h, 820°C-850°C for 1-8h, and then cooled; The amount of the mixed deoxidizer does not exceed 0.1% of the mass of titanium hydride; The mixed deoxidizer comprises boride, hydride and titanium dichloride; the mass ratio of boride, hydride and titanium dichloride is 1-4:1-2:1; Alternatively, the mixed deoxidizer comprises hydride, carbide and titanium dichloride; the mass ratio of hydride, carbide and titanium dichloride is 2-3:2-4:1; The boride is CaB6; the carbide is CaC2; and the hydride is CaH2.

2. The use of the mixed deoxidizer in HDH according to claim 1, characterized in that: The D90 of the mixed deoxidizer is less than 1 μm and is not zero.

3. The use of the mixed deoxidizer in HDH according to claim 1, characterized in that: The D50 of the mixture obtained by mixing the mixed deoxidizer and titanium hydride is ≤25 μm and is not zero.

4. The use of the mixed deoxidizer in HDH according to claim 1, characterized in that: The method for mixing the mixed deoxidizer and titanium hydride is ball milling, the ball-to-material ratio of the ball milling process is 3-15:1, the rotation speed is 200-800r / min, and the ball milling time is 2-24h.

5. The use of the mixed deoxidizer in HDH according to claim 1, characterized in that: The oxygen content of the product is ≤2000ppm.

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