A method for preparing titanium alloy based on titanium hydride powder

Abstract

The present invention relates to the field of titanium alloy production, and specifically discloses a titanium alloy preparation method based on titanium hydride powder, comprising the following steps: (1) using titanium hydride powder as a raw material to prepare titanium hydride ultrafine powder; (2) uniformly mixing the titanium hydride ultrafine powder with alloy element powder, wherein the alloy element powder is a mixture of Al powder, Sn powder, Zr powder, Mo powder and Si powder; (3) loading the mixed raw materials into a mold and pressing them into shape; (4) placing the molded raw materials in a vacuum sintering furnace for vacuum sintering to obtain a titanium alloy. The titanium alloy prepared by the method has uniform alloy structure, excellent mechanical properties and simple process, and effectively solves the problems that titanium powder is easily oxidized, the process is complicated, and the alloy structure is uniform and the mechanical properties are poor in the process of preparing titanium alloy.

Description

Technical Field

[0001] The invention relates to the field of titanium alloy production, and in particular to a method for preparing a titanium alloy based on titanium hydride powder. Background Art

[0002] Titanium alloy is an alloy composed of titanium and other elements. It generally has excellent properties of high strength, good corrosion resistance and high heat resistance. It is mainly used in aerospace, petrochemical, automobile manufacturing and other fields, and has broad application prospects. In the prior art, the titanium source of titanium alloy is mostly titanium powder, which has a high cost, and the prepared alloy composition is uneven and the mechanical properties are poor. In addition, titanium powder is easily oxidized during the processing, which brings about the defect of complex process. In the prior art, there is a preparation process using titanium hydride powder as the titanium source, which has the current situation of uneven alloy structure and grains, which also affects the performance of titanium alloy products. Summary of the invention

[0003] In view of the above situation, in order to overcome the defects of the prior art, the present invention provides a method for preparing a titanium alloy based on titanium hydride powder, which has uniform alloy structure, excellent performance and simple process.

[0004] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0005] A method for preparing a titanium alloy based on titanium hydride powder comprises the following steps:

[0006] Step 1: Using titanium hydride powder as raw material, preparing titanium hydride ultrafine powder;

[0007] Step 2: uniformly mix titanium hydride ultrafine powder and alloy element powder, wherein the alloy element powder is a mixture of Al powder, Sn powder, Zr powder, Mo powder and Si powder;

[0008] Step 3: Put the raw materials mixed in step 2 into a mold and press into shape;

[0009] Step 4: placing the raw material formed in step 3 in a vacuum sintering furnace for vacuum sintering to obtain a titanium alloy.

[0010] As a further solution of the present invention, the preparation method of the titanium hydride ultrafine powder is: adding titanium hydride powder to the grinding tank of a planetary ball mill, then adding grinding body and dispersant, grinding at a rotation speed of 120-500r / min and a grinding time of 3-10h to obtain titanium hydride ultrafine powder.

[0011] As a further solution of the present invention, the mass ratio of titanium hydride powder to grinding body in the grinding jar is 1:2-1:5, and the grinding body is one or a combination of tungsten carbide balls, tungsten carbide columns, zirconia balls, and zirconia columns.

[0012] As a further solution of the present invention, the grinding body is a combination of tungsten carbide balls and tungsten carbide columns, and the mass gradation of the tungsten carbide balls in the grinding body is 10mm balls: 5mm balls: 1mm balls = 2:5:3; the dimensions of the tungsten carbide columns are: bottom circle diameter of 1-3mm, length of 1-5mm; the mass ratio of tungsten carbide balls to tungsten carbide columns is 2:1-5:1.

[0013] As a further solution of the present invention, the dispersant is one of triethanolamine and polyethylene glycol, and the dosage of the dispersant is 0.5%-2% of the mass of the titanium hydride powder.

[0014] As a further solution of the present invention, the mass ratio of the titanium hydride ultrafine powder to the alloy element powder is titanium hydride ultrafine powder: Al powder: Sn powder: Zr powder: Mo powder: Si powder = 86.67: 6.14: 2.69: 3.74: 0.48: 0.28.

[0015] As a further solution of the present invention, the equipment used for mixing the ultrafine titanium hydride powder and the alloy element powder in step 2 is a drum mixer.

[0016] The technical solution of the present invention also includes that the pressing method in step three is cold isostatic pressing, the molding pressure is 220-260 MPa, and the holding time is 2-4 minutes.

[0017] As a further solution of the present invention, the process of vacuum sintering in step 4 is:

[0018] S1: first evacuate the room temperature, then heat the temperature from room temperature to 150°C at a rate of 5°C / min, and keep the temperature for 30 min;

[0019] S2: Heating to 450°C, heating rate 7°C / min, keeping temperature for 30 min;

[0020] S3: Heating to 800°C at a rate of 8°C / min and keeping at this temperature for 30 min;

[0021] S4: Heating to 1150°C at a rate of 10°C / min and keeping at this temperature for 5h;

[0022] S5: After step S4, the furnace is cooled to 700°C, and then filled with argon to quickly cool to room temperature.

[0023] The beneficial effects of the present invention are:

[0024] Compared with the prior art, the purpose of the present invention is to provide a titanium alloy preparation method based on titanium hydride powder with uniform alloy structure, excellent performance and simple process. In order to achieve the above technical effects, the present invention first grinds the titanium hydride powder. The titanium hydride ultrafine powder obtained by the grinding process can significantly improve the uniformity of the alloy structure and grains under the microstructure, thereby effectively improving the overall performance of the titanium alloy product; secondly, the present invention uses titanium hydride as the titanium source, which has lower cost, more stable performance, is not easy to be contaminated, and effectively avoids the reduction of titanium alloy performance due to oxidation of titanium powder, while simplifying the process flow, and titanium hydride is conducive to promoting sintering. Direct dehydrogenation during high-temperature sintering can reduce the oxygen content in the alloy and the impurity content, thereby improving the traditional arc furnace smelting with titanium powder as raw material under argon protection, which is prone to uneven alloy composition and microstructure; finally, the present invention uses Al powder, Sn powder, Zr powder, Mo powder, S i powder is an alloy component. By optimizing the ratio and the synergistic effect of various elements, it plays a role in supplementing and strengthening the titanium matrix, and can further improve the overall performance of titanium alloy products. The titanium alloy has a tensile strength of 465MPa and a hardness of 299HV, and has excellent mechanical properties. DETAILED DESCRIPTION

[0025] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. 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 should fall within the scope of protection of the present invention.

[0026] Embodiment 1:

[0027] This embodiment is a method for preparing a titanium alloy based on titanium hydride powder, comprising the following steps:

[0028] Step 1: Using titanium hydride powder as raw material, preparing titanium hydride ultrafine powder; the step is to load the titanium hydride powder into the grinding tank of the planetary ball mill, add the grinding body, and add triethanolamine as a dispersant, and the amount of the dispersant is 0.5% of the mass of the titanium hydride powder; the mass ratio of the titanium hydride powder to the grinding body in the grinding tank is 1:2, the rotation speed of the planetary ball mill is 200r / min, and the grinding time is 10h;

[0029] The grinding body is a combination of tungsten carbide balls and tungsten carbide columns. The mass gradation of the tungsten carbide balls in the grinding body is 10mm balls: 5mm balls: 1mm balls = 2:5:3; the size of the tungsten carbide columns is: bottom circle diameter is 3mm, length is 5mm; the mass ratio of tungsten carbide balls to tungsten carbide columns is 2:1.

[0030] Step 2: Mix the titanium hydride ultrafine powder and the alloy element powder evenly through a drum mixer, wherein the alloy element powder is a mixture of Al powder, Sn powder, Zr powder, Mo powder, and Si powder; the mass ratio of the titanium hydride ultrafine powder to the alloy element powder is titanium hydride ultrafine powder: Al powder: Sn powder: Zr powder: Mo powder: Si powder = 86.67: 6.14: 2.69: 3.74: 0.48: 0.28.

[0031] Step 3: Place the raw materials mixed in step 2 into a mold and perform cold isostatic pressing. The molding pressure is 240 MPa and the holding time is 3 minutes.

[0032] Step 4: Place the raw material formed in step 3 in a high temperature furnace for vacuum sintering to obtain a titanium alloy. The vacuum sintering process is as follows:

[0033] S1: first evacuate the room temperature, then heat the temperature from room temperature to 150°C at a rate of 5°C / min, and keep the temperature for 30 min;

[0034] S2: Heating to 450°C, heating rate 7°C / min, keeping temperature for 30 min;

[0035] S3: Heating to 800°C at a rate of 8°C / min and keeping at this temperature for 30 min;

[0036] S4: Heating to 1150°C at a rate of 10°C / min and keeping at this temperature for 5h;

[0037] S5: After step S4, the furnace is cooled to 700°C, and then filled with argon to quickly cool to room temperature.

[0038] Embodiment 2:

[0039] This embodiment is a method for preparing a titanium alloy based on titanium hydride powder, comprising the following steps:

[0040] Step 1: Using titanium hydride powder as raw material, preparing titanium hydride ultrafine powder; the step is to load the titanium hydride powder into the grinding tank of the planetary ball mill, add the grinding body, and add triethanolamine as a dispersant, and the amount of the dispersant is 1% of the mass of the titanium hydride powder; the mass ratio of the titanium hydride powder to the grinding body in the grinding tank is 1:5, the rotation speed of the planetary ball mill is 500r / min, and the grinding time is 3h;

[0041] Among them, the grinding body is a combination of tungsten carbide balls and tungsten carbide columns. The mass gradation of the tungsten carbide balls in the grinding body is 10mm balls: 5mm balls: 1mm balls = 2:5:3; the size of the tungsten carbide columns is: bottom circle diameter is 3mm, length is 5mm; the mass ratio of tungsten carbide balls to tungsten carbide columns is 3:1.

[0042] Step 2: Mix the titanium hydride ultrafine powder and the alloy element powder evenly through a drum mixer, wherein the alloy element powder is a mixture of Al powder, Sn powder, Zr powder, Mo powder, and Si powder; the mass ratio of the titanium hydride ultrafine powder to the alloy element powder is titanium hydride ultrafine powder: Al powder: Sn powder: Zr powder: Mo powder: Si powder = 86.67: 6.14: 2.69: 3.74: 0.48: 0.28.

[0043] Step 3: Place the raw materials mixed in step 2 into a mold and perform cold isostatic pressing. The molding pressure is 240 MPa and the holding time is 3 minutes.

[0044] Step 4: Place the raw material formed in step 3 in a high temperature furnace for vacuum sintering to obtain a titanium alloy. The vacuum sintering process is as follows:

[0045] S1: first evacuate the room temperature, then heat the temperature from room temperature to 150°C at a rate of 5°C / min, and keep the temperature for 30 min;

[0046] S2: Heating to 450°C, heating rate 7°C / min, keeping temperature for 30 min;

[0047] S3: Heating to 800°C at a rate of 8°C / min and keeping at this temperature for 30 min;

[0048] S4: Heating to 1150°C at a rate of 10°C / min and keeping at this temperature for 5h;

[0049] S5: After step S4, the furnace is cooled to 700°C, and then filled with argon to quickly cool to room temperature.

[0050] Embodiment 3:

[0051] This embodiment is a method for preparing a titanium alloy based on titanium hydride powder, comprising the following steps:

[0052] Step 1: Using titanium hydride powder as raw material, preparing titanium hydride ultrafine powder; the step is to load the titanium hydride powder into the grinding tank of the planetary ball mill, add the grinding body, and add polyethylene glycol as a dispersant, and the amount of the dispersant is 2% of the mass of the titanium hydride powder; the mass ratio of the titanium hydride powder to the grinding body in the grinding tank is 1:3, the rotation speed of the planetary ball mill is 400r / min, and the grinding time is 8h;

[0053] Among them, the grinding body is a combination of tungsten carbide balls and tungsten carbide columns. The mass gradation of the tungsten carbide balls in the grinding body is 10mm balls: 5mm balls: 1mm balls = 2:5:3; the size of the tungsten carbide columns is: bottom circle diameter is 2mm, length is 4mm; the mass ratio of tungsten carbide balls to tungsten carbide columns is 3:1.

[0054] Step 2: Mix the titanium hydride ultrafine powder and the alloy element powder evenly through a drum mixer, wherein the alloy element powder is a mixture of Al powder, Sn powder, Zr powder, Mo powder, and Si powder; the mass ratio of the titanium hydride ultrafine powder to the alloy element powder is titanium hydride ultrafine powder: Al powder: Sn powder: Zr powder: Mo powder: Si powder = 86.67: 6.14: 2.69: 3.74: 0.48: 0.28.

[0055] Step 3: Place the raw materials mixed in step 2 into a mold and perform cold isostatic pressing. The molding pressure is 240 MPa and the holding time is 3 minutes.

[0056] Step 4: Place the raw material formed in step 3 in a high temperature furnace for vacuum sintering to obtain a titanium alloy. The vacuum sintering process is as follows:

[0057] S1: first evacuate the room temperature, then heat the temperature from room temperature to 150°C at a rate of 5°C / min, and keep the temperature for 30 min;

[0058] S2: Heating to 450°C, heating rate 7°C / min, keeping temperature for 30 min;

[0059] S3: Heating to 800°C at a rate of 8°C / min and keeping at this temperature for 30 min;

[0060] S4: Heating to 1150°C at a rate of 10°C / min and keeping at this temperature for 5h;

[0061] S5: After step S4, the furnace is cooled to 700°C, and then filled with argon to quickly cool to room temperature.

[0062] The titanium alloys prepared in Examples 1-3 were tested for density, tensile strength and hardness. The test results are shown in the following table:

[0063] sample <![CDATA[Density of titanium alloy / g·cm -3 > Compressive strength / MPa Hardness / HV Example 1 4.15 468 302 Example 2 3.94 465 299 Example 3 4.20 472 310

[0064] Referring to the data in the above table, it can be known that the titanium alloy prepared in the present invention has a tensile strength of not less than 465 MPa and a hardness of not less than 299 HV, and has excellent mechanical properties.

[0065] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0066] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the invention or exceed the scope defined by the claims, they shall all fall within the protection scope of the present invention.

Claims

1. A method for preparing a titanium alloy based on titanium hydride powder, characterized in that: The following steps are involved: Step 1: Using titanium hydride powder as raw material, preparing titanium hydride ultrafine powder; Step 2: uniformly mix titanium hydride ultrafine powder and alloy element powder, wherein the alloy element powder is a mixture of Al powder, Sn powder, Zr powder, Mo powder and Si powder; Step 3: Put the raw materials mixed in step 2 into a mold and press them into shape; Step 4: placing the raw material formed in step 3 in a vacuum sintering furnace for vacuum sintering to obtain a titanium alloy.

2. A method for preparing a titanium alloy based on titanium hydride powder according to claim 1, characterized in that: The preparation method of the titanium hydride ultrafine powder is as follows: adding titanium hydride powder into a grinding tank of a planetary ball mill, then adding a grinding body and a dispersant, and grinding at a rotation speed of 120-500 r / min and a grinding time of 3-10 h to obtain the titanium hydride ultrafine powder.

3. A method for preparing a titanium alloy based on titanium hydride powder according to claim 2, characterized in that: The mass ratio of titanium hydride powder to grinding body in the grinding jar is 1:2-1:5, and the grinding body is one or a combination of tungsten carbide balls, tungsten carbide columns, zirconium oxide balls, and zirconium oxide columns.

4. A method for preparing a titanium alloy based on titanium hydride powder according to claim 3, characterized in that: The grinding body is a combination of tungsten carbide balls and tungsten carbide columns. The mass gradation of the tungsten carbide balls in the grinding body is 10mm balls: 5mm balls: 1mm balls = 2:5:3; the size of the tungsten carbide columns is: the bottom circle diameter is 1-3mm, the length is 1-5mm; the mass ratio of tungsten carbide balls to tungsten carbide columns is 2:1-5:

1.

5. The method for preparing a titanium alloy based on titanium hydride powder according to claim 2, characterized in that: The dispersant is one of triethanolamine and polyethylene glycol, and the dosage of the dispersant is 0.5%-2% of the mass of the titanium hydride powder.

6. The method for preparing a titanium alloy based on titanium hydride powder according to claim 1, characterized in that: The mass ratio of the titanium hydride ultrafine powder to the alloy element powder is titanium hydride ultrafine powder: Al powder: Sn powder: Zr powder: Mo powder: Si powder = 86.67: 6.14: 2.69: 3.74: 0.48: 0.

28.

7. The method for preparing a titanium alloy based on titanium hydride powder according to claim 1, characterized in that: The equipment used for mixing the titanium hydride ultrafine powder and the alloy element powder in the step 2 is a drum mixer.

8. The method for preparing a titanium alloy based on titanium hydride powder according to claim 1, characterized in that: The pressing method in step 3 is cold isostatic pressing, the molding pressure is 220-260 MPa, and the holding time is 2-4 minutes.

9. The method for preparing a titanium alloy based on titanium hydride powder according to claim 1, characterized in that: The process of vacuum sintering in step 4 is: S1: first evacuate the room temperature, then heat the temperature from room temperature to 150°C at a rate of 5°C / min, and keep the temperature for 30 min; S2: Heating to 450°C, heating rate 7°C / min, keeping temperature for 30 min; S3: Heating to 800°C at a rate of 8°C / min and keeping at this temperature for 30 min; S4: Heating to 1150°C at a rate of 10°C / min and keeping at this temperature for 5h; S5: After step S4, the furnace is cooled to 700°C, and then filled with argon to quickly cool to room temperature.