A titanium-aluminum-niobium alloy friction plate, its preparation method and application

Abstract

This invention provides a titanium-aluminum-niobium alloy friction pad, its preparation method, and its application, relating to the field of alloy materials technology. The titanium-aluminum-niobium alloy friction pad provided by this invention comprises the following elements by mass percentage: Al 8.5–25.5%, Nb 16–38%, Ce 2–6%, Gd 2–6%, Y 1–3%, La 0.5–1.5%, with the balance being Ti. This invention introduces multiple rare earth elements Ce, Gd, Y, and La into the titanium-aluminum-niobium alloy, forming a dispersed high-hardness rare earth oxide reinforcement in the alloy. The resulting alloy exhibits high hardness, good wear resistance, and a stable coefficient of friction. This invention also provides a preparation method for the titanium-aluminum-niobium alloy friction pad, employing powder metallurgy. Through cold isostatic pressing followed by atmospheric pressure sintering, a high-density rare earth titanium-aluminum-niobium alloy friction pad is obtained, exhibiting advantages such as high wear resistance and corrosion resistance, low cost, good consistency, and ease of industrial-scale mass production.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of alloy materials, and particularly relates to a titanium-aluminum-niobium alloy friction plate and a preparation method and application thereof. BACKGROUND

[0002] Vehicle clutch friction plates, such as tractor clutch friction plates, are key components for ensuring smooth starting, smooth gear shifting and sufficient power of tractors. Under long-time work or extreme working conditions, the friction plate is prone to abnormal friction, causing ablation, slippage and warping and other faults. With the continuous accumulation of clutch working time, the surface of the friction plate can appear serious mechanical wear, resulting in a gradual decrease in the thickness of the friction material and eventually leading to wear failure. In addition, for large tractors with uninterrupted power, strong slippage occurs during the process of changing sections or gears, generating a large amount of heat, which causes the chemical substances in the friction material to gradually decompose and carbonize, aggravating the wear and eventually leading to failure. Therefore, in order to prolong the service life of the friction plate and improve the safety of the clutch, the friction material needs to have stable friction coefficient, high mechanical strength, good wear resistance and high-temperature resistance and other properties. At present, the commonly used friction plate material is copper-based alloy, which has good wear resistance and good thermal conductivity.

[0003] Titanium-aluminum-niobium alloy belongs to intermetallic compound-based alloy, has the characteristics of low density compared with copper, high elastic modulus, high high-temperature strength, strong anti-creep ability, strong oxidation resistance and good corrosion resistance in oily medium, and has been widely used in many fields. However, there is no report on the friction plate material of titanium-aluminum-niobium alloy. SUMMARY

[0004] Therefore, the purpose of the present application is to provide a titanium-aluminum-niobium alloy friction plate and a preparation method and application thereof. The titanium-aluminum-niobium alloy friction plate provided by the present application has high hardness, good wear resistance and stable friction coefficient, and can be applied to vehicle clutches.

[0005] In order to achieve the above-mentioned purpose of the application, the present application provides the following technical scheme:

[0006] The present application provides a titanium-aluminum-niobium alloy friction plate, which comprises the following mass percentages of elements: Al 8.5-25.5%, Nb 16-38%, Ce 2-6%, Gd 2-6%, Y 1-3%, La 0.5-1.5%, and the balance being Ti.

[0007] The present application provides a preparation method of the titanium-aluminum-niobium alloy friction plate described in the above technical scheme, comprising the following steps:

[0008] Ti powder, Al-60Nb alloy powder, Nb powder and Al-20Ce-20Gd-10Y-5La alloy powder are mixed and ball milled to obtain a mixed powder; the mass percentage of the Ti powder, Al-Nb alloy powder, Nb powder and Al-20Ce-20Gd-10Y-5La alloy powder in the mixed powder is 20-70%, 10-30%, 10-20% and 10-30%, respectively;

[0009] The mixed powder is cold isostatic pressed to obtain a shaped material;

[0010] The shaped material is subjected to normal pressure programmed sintering, which comprises: under a protective atmosphere, the shaped material is heated from room temperature to a first temperature at a first heating rate, then heated from the first temperature to a second temperature at a second heating rate, and then heated from the second temperature to a third temperature at a third heating rate, and after holding at the third temperature, the shaped material is cooled to obtain a titanium-aluminum-niobium alloy friction plate; the first heating rate, the second heating rate and the third heating rate are 20-40 ℃ / min, 5-10 ℃ / min and 1-5 ℃ / min, respectively; and the first temperature, the second temperature and the third temperature are 600-700 ℃, 950-1100 ℃ and 1400-1500 ℃, respectively.

[0011] Preferably, the particle size of the Ti powder is 20-50 μm, the particle size of the Al-60Nb alloy powder is 20-75 μm, the particle size of the Nb powder is 5-25 μm, and the particle size of the Al-20Ce-20Gd-10Y-5La alloy powder is 20-200 μm.

[0012] Preferably, the ball milling medium is polyethylene glycol or toluene, and the volume ratio of the ball milling medium to the mixed powder is (1-5):1.

[0013] Preferably, the rotation speed of the ball milling is 100-200 r / min, and the time is 60-240 min.

[0014] Preferably, the pressure of the cold isostatic pressing is 150-400 MPa, and the pressure holding time is 10-60 min.

[0015] Preferably, the protective atmosphere is Ar gas, and the flow rate of the Ar gas is 100-400 mL / min.

[0016] Preferably, the holding time is 4-8 h.

[0017] Preferably, the cooling is furnace cooling.

[0018] The application provides application of the titanium-aluminum-niobium alloy friction plate in a vehicle clutch.

[0019] The application provides a titanium-aluminum-niobium alloy friction plate, which comprises the following elements in mass percentage: Al 8.5-25.5%, Nb 16-38%, Ce 2-6%, Gd 2-6%, Y 1-3%, La 0.5-1.5%, and the balance of Ti. The application introduces multiple rare earth elements Ce, Gd, Y and La into the titanium-aluminum-niobium alloy. The addition of the rare earth elements can form high-hardness rare earth oxides as the strengthening phase of the matrix, thereby improving the hardness of the alloy and the wear resistance of the alloy. The multiple rare earth oxides are firmly combined with the matrix, eliminating the weak connection effect of the grain boundary and improving the fracture toughness of the titanium alloy friction plate. The titanium alloy friction plate can withstand the impact load during the use of the friction plate. The pores between the single rare earth oxide and the matrix can become a crack source, thereby reducing the fracture toughness of the friction plate. In addition, the high-melting-point rare earth oxides improve the thermal strength of the alloy, thereby avoiding the failure and fracture of the alloy at high temperature caused by the heat generated during the friction process. The multiple rare earth elements introduced in the application can form multiple composite rare earth oxides, thereby avoiding the formation of multiple dispersed rare earth oxides, ensuring the uniformity of the surface structure and hardness of the alloy, avoiding the first failure at the position with low hardness, and the uniform surface hardness is conducive to the stability of the friction coefficient of the alloy. Therefore, the titanium-aluminum-niobium alloy friction plate provided by the application has high hardness, good wear resistance and stable friction coefficient.

[0020] The application provides the preparation method of the titanium-aluminum-niobium alloy friction plate, and the powder metallurgy technology with low cost advantage is used to prepare the friction plate material, the powder metallurgy near net shape technology is used to prepare the special-shaped part, the machining amount is reduced, the raw material utilization rate is improved, the application cost of the titanium alloy is reduced, and the energy consumption in the preparation process is reduced by the normal pressure sintering method. Moreover, the multi-step sintering is carried out under the normal pressure by using the programmed temperature rising mode, different temperature rising rates are used in different temperature rising stages of sintering, the diffusion time of each rare earth in the multi-element rare earth aluminum alloy to titanium is adjusted, and the size of the rare earth oxide is accurately controlled. Specifically, in the temperature range of 600-700 DEG C, the La element has diffused into the Ti particles, the Ce, Gd and Y elements have not diffused, at this time, the faster temperature rising rate is used to avoid the generation of La2O3 at low temperature, so that the oxygen exists in the matrix phase in the form of solid solution; at 950-1100 DEG C, the Ce element has diffused into the Ti particles, the Gd and Y elements have not diffused, at this time, the moderate temperature rising rate is used to inhibit the growth of La2O3 particles, and at the same time, the Ce element diffuses into the La2O3 particles to form (Ce, La)2O3 composite oxide; at 1400-1500 DEG C, the Gd and Y elements have diffused into the Ti particles, at this time, the slower temperature rising rate is used to promote the Gd and Y to fully diffuse into (Ce, La)2O3 to form (Ce, Gd, Y, La)2O3 multi-element composite rare earth oxide, and the dispersed multi-element rare earth oxide is avoided. The friction plate material prepared by the application has uniform and dense structure, high wear resistance and corrosion resistance, low cost, good consistency, and is easy to realize the low-cost batch production of special-shaped parts such as clutch friction plates.

[0021] The results of the examples show that the titanium-aluminum-niobium alloy friction plate provided by the application has the density of more than 99%, the tensile strength at 600 DEG C is greater than 500 MPa, the Rockwell hardness reaches 55-65 HRC, the friction coefficient is stably kept at 0.5-0.7, the wear rate is 9.14*10 –5 mm 3 ·m –1 ·N –1 ~1.52*10 –4 mm 3 ·m –1 ·N –1 . BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 It is the 500 times scanning electron microscope graph of the tractor clutch friction plate material obtained in Example 1;

[0023] Figure 2 It is the tensile stress-strain curve of the tractor clutch friction plate material obtained in Example 3 at 600 DEG C. DETAILED DESCRIPTION

[0024] The application provides a titanium-aluminum-niobium alloy friction plate, which comprises the following elements in mass percentage: Al 8.5-25.5%, Nb 16-38%, Ce 2-6%, Gd 2-6%, Y 1-3%, La 0.5-1.5%, and the balance is Ti.

[0025] In the application, the mass percentage of Al is preferably 15-25%, the mass percentage of Nb is preferably 20-30%, the mass percentage of Ce is preferably 4-6%, the mass percentage of Gd is preferably 4-6%, the mass percentage of Y is preferably 2-2.8%, and the mass percentage of La is preferably 1-1.4%.

[0026] The titanium-aluminum-niobium alloy belongs to an intermetallic compound-based alloy, has high hardness, excellent high-temperature performance, excellent oxidation resistance and corrosion resistance, and the application of multiple rare earth elements Ce, Gd, Y and La in the titanium-aluminum-niobium alloy can form high-hardness rare earth oxides, further improve the hardness, wear resistance and high-temperature strength of the alloy, and make the alloy have a stable friction coefficient.

[0027] The application provides a preparation method of the titanium-aluminum-niobium alloy friction plate.

[0028] The Ti powder, Al-60Nb alloy powder, Nb powder and Al-20Ce-20Gd-10Y-5La alloy powder are mixed and ball milled to obtain a mixed powder; the mass percentages of the Ti powder, Al-60Nb alloy powder, Nb powder and Al-20Ce-20Gd-10Y-5La alloy powder in the mixed powder are 20-70%, 10-30%, 10-20% and 10-30%, respectively.

[0029] The mixed powder is cold isostatic pressed to obtain a formed material.

[0030] The formed material is subjected to normal-pressure programmed sintering, and the normal-pressure programmed sintering comprises the following steps: under a protective atmosphere, the formed material is heated from room temperature to a first temperature at a first heating rate, then heated from the first temperature to a second temperature at a second heating rate, and then heated from the second temperature to a third temperature at a third heating rate; after being kept at the third temperature, the formed material is cooled to obtain a titanium-aluminum-niobium alloy friction plate; the first heating rate, the second heating rate and the third heating rate are 20-40 ℃ / min, 5-10 ℃ / min and 1-5 ℃ / min, respectively; and the first temperature, the second temperature and the third temperature are 600-700 ℃, 950-1100 ℃ and 1400-1500 ℃, respectively.

[0031] In the present application, the raw materials involved are all commercially available products well known to those skilled in the art, unless otherwise specified. In the examples of the present application, the Al-60Nb alloy is purchased from Shanghai Yunfu Nanometer Technology Co., Ltd., and the Al-20Ce-20Gd-10Y-5La alloy is purchased from Hunan Nonferrous Metals Research Institute.

[0032] In the present application, the Ti powder, the Al-60Nb alloy powder, the Nb powder and the Al-20Ce-20Gd-10Y-5La alloy powder are mixed and ball-milled to obtain a mixed powder. In the present application, the mass percentage of the Ti powder, the Al-60Nb alloy powder, the Nb powder and the Al-20Ce-20Gd-10Y-5La alloy powder in the mixed powder is 20-70%, 10-30%, 10-20% and 10-30%, respectively, and is further preferably 30-50%, 10-25%, 10-15% and 20-30%, respectively. In the present application, the Al-based master alloy powder is used as the raw material instead of Al powder to provide Al element, and the Al-20Ce-20Gd-10Y-5La alloy powder is added to increase the density of the alloy sintered under normal pressure, form rare earth oxide particles, and improve the hardness and wear resistance of the alloy. In the present application, the particle size of the Ti powder is preferably 20-50 μm, and more preferably 25-45 μm, the particle size of the Al-60Nb alloy powder is preferably 20-75 μm, and more preferably 25-50 μm, the particle size of the Nb powder is preferably 5-25 μm, and more preferably 10-25 μm, and the particle size of the Al-20Ce-20Gd-10Y-5La alloy powder is preferably 20-200 μm, and more preferably 25-120 μm.

[0033] In the present application, the ball-milling medium is preferably polyethylene glycol or toluene, and the volume ratio of the ball-milling medium to the mixed powder obtained by mixing is preferably (1-5):1, and more preferably (3-4):1. The rotation speed of the ball-milling is preferably 100-200 r / min, and more preferably 150-200 r / min, and the time is preferably 60-240 min, and more preferably 100-200 min. In the present application, the ball-milling is preferably carried out in a planetary ball mill. In the present application, the Al-20Ce-20Gd-10Y-5La rare earth alloy powder is broken and uniformly dispersed in the Ti, Al-60Nb and Nb powders by ball-milling, so that the generated rare earth oxide is prevented from existing in the form of agglomeration. After the ball-milling, the mixed powder after the ball-milling is preferably dried. In the present application, the drying method is not particularly limited, and any drying method well known to those skilled in the art can be used.

[0034] After obtaining the mixed powder, the mixed powder is cold isostatic pressed to obtain a shaped material. In the present application, the pressure of the cold isostatic pressing is preferably 150-400 MPa, more preferably 200-300 MPa, and the pressure holding time is preferably 10-60 min, more preferably 40-60 min; when the titanium-aluminum-niobium alloy friction plate is used for a vehicle clutch, the mold used for the cold isostatic pressing is preferably a clutch friction plate mold.

[0035] After obtaining the shaped material, the shaped material is subjected to normal pressure programmed sintering to obtain a titanium-aluminum-niobium alloy friction plate. In the present application, the normal pressure programmed sintering is preferably carried out in a tube furnace. In the present application, the normal pressure programmed sintering comprises: under a protective atmosphere, heating the shaped material from room temperature to a first temperature at a first heating rate, then heating the shaped material from the first temperature to a second temperature at a second heating rate, and then heating the shaped material from the second temperature to a third temperature at a third heating rate, and after holding at the third temperature, cooling. In the present application, the protective atmosphere is preferably Ar gas, and the flow rate of the Ar gas is preferably 100-400 mL / min, more preferably 150-350 mL / min. In the present application, the vacuum degree in the tube furnace is preferably reduced to 2x10 -3 ~4x10 -3 Pa, and after the flow of Ar gas is introduced into the furnace to stabilize the gas pressure in the furnace at 1x10 5 Pa (i.e. normal pressure), the Ar gas flow rate is kept at a constant value of 100-400 mL / min, and the normal pressure programmed sintering is carried out under this condition. In the present application, the first heating rate is 20-40 ℃ / min, preferably 20-35 ℃ / min, the first temperature is 600-700 ℃, more preferably 600-650 ℃; the second heating rate is 5-10 ℃ / min, preferably 6-8 ℃ / min, the second temperature is 950-1100 ℃, preferably 950-1000 ℃; the third heating rate is 1-5 ℃ / min, preferably 2-3 ℃ / min, and the third temperature is 1400-1500 ℃, preferably 1400-1460 ℃. In the present application, the holding time is preferably 4-8 h; and the cooling is preferably furnace cooling. In the present application, the aluminum-multinary rare earth alloy is used as the raw material to control the diffusion time of each rare earth into titanium by changing the heating rate, and to avoid excessive growth of oxides, thereby forming multinary rare earth oxides connecting titanium grains near the grain boundaries of the matrix phase, and the rare earth oxides extend into the grain interior, forming a good bonding interface with the matrix, thereby improving the hardness and high temperature strength of the alloy, and minimizing the pores near the grain boundaries; in addition, the addition of rare earth can purify the oxygen in the matrix, inhibit the formation of brittle Ti3Al phase, improve the brittleness of the alloy, and reduce the difficulty of finishing of the alloy.

[0036] The application can obtain high-density alloy by cold isostatic pressing and normal pressure sintering, and the normal pressure sintering is multi-step sintering under normal pressure by adopting programmed heating, different heating rates are adopted in different heating stages of sintering, the diffusion time of each rare earth in the multi-element rare earth aluminum alloy to titanium can be adjusted, the size of rare earth oxide can be accurately controlled, the porosity near the grain boundary can be reduced, the sintered titanium alloy has high density, good plasticity at room temperature, high hardness, good wear resistance and high high-temperature strength.

[0037] The application provides application of the titanium-aluminum-niobium alloy friction plate in a vehicle clutch.

[0038] In order to further illustrate the application, the titanium-aluminum-niobium alloy friction plate, the preparation method and the application thereof provided by the application are described in detail below with examples, but they should not be understood as limitation to the protection scope of the application.

[0039] Example 1

[0040] Alloy composition: Ti-17Al-22Nb-4Ce-4Gd-2Y-1La (mass fraction, %)

[0041] (1) Ti powder, Al-60Nb (mass fraction, %) intermediate alloy powder, Nb powder and Al-20Ce-20Gd-10Y-5La (mass fraction, %) alloy powder are weighed according to the proportion, and the mass percentage is: Ti powder 50%, Al-60Nb alloy powder 20%, Nb powder 10% and Al-20Ce-20Gd-10Y-5La alloy powder 20%, wherein the particle size of the Ti powder is 45 μm, the particle size of the Al-60Nb alloy powder is 75 μm, the particle size of the Nb powder is 10 μm, and the particle size of the Al-20Ce-20Gd-10Y-5La alloy powder is 120 μm.

[0042] (2) Toluene is used as the ball milling medium, the volume ratio of the ball milling medium to the powder is 3:1, and the Ti powder, the Al-60Nb alloy powder, the Nb powder and the Al-20Ce-20Gd-10Y-5La alloy powder are fully mixed by using a planetary ball mill at a rotating speed of 200 r / min for 100 min.

[0043] (3) The powder obtained in step (2) is dried and then put into a tractor clutch friction plate mold for cold isostatic pressing, and the forming pressure is 200 MPa and the pressure maintaining time is 60 min.

[0044] (4) Put the tractor clutch plate blank obtained in step (3) into a sintering furnace for programmed heating, reduce the vacuum degree in the furnace to 2×10 -3 Pa, after the Ar gas flow rate is kept at a constant value of 150 mL / min, the green compact is first heated from room temperature to 600℃ at a heating rate of 20℃ / min; 5

[0045] The first heated green compact is second heated to 1000℃ at a heating rate of 10℃ / min in the flowing Ar atmosphere;

[0046] The second heated green compact is third heated to 1400℃ at a heating rate of 5℃ / min in the flowing Ar atmosphere;

[0047] Keep the temperature at 1400℃ for 8h, and cool down with the furnace.

[0048] The obtained tractor clutch plate sintered blank is processed by precision turning, and finally the tractor clutch plate is obtained.

[0049] Figure 1 The microstructure photo of the tractor clutch plate material obtained in Example 1 is shown in Figure 1. Figure 1 It can be seen that the hard rare earth oxides are uniformly dispersed on the matrix, which is beneficial to improve the surface hardness and wear resistance.

[0050] The Rockwell hardness of the tractor clutch plate material obtained in Example 1 is 60HRC, the friction coefficient and wear rate of the alloy are tested by using a friction and wear tester, the friction pair uses a Si3N4 ball with a diameter of 9.525mm, the load is 2N, the sliding speed is 7.4cm / s, the test time is 20min, the room temperature friction coefficient of the obtained alloy is 0.68, and the room temperature wear rate is 9.77×10 –5 mm 3 ·m –1 ·N –1 The fracture toughness of the obtained alloy is 5.23MPa·m 1 / 2 .

[0051] Example 2

[0052] Alloy composition: Ti-23.5Al-30Nb-6Ce-6Gd-3Y-1.5La (mass fraction, %)

[0053] ​(1) Ti powder, Al-60Nb (mass fraction, %) intermediate alloy powder, Nb powder and Al-20Ce-20Gd-10Y-5La (mass fraction, %) alloy powder are weighed according to the proportion, and the mass percentage is: Ti powder 30%, Al-60Nb alloy powder 25%, Nb powder 15%, and Al-20Ce-20Gd-10Y-5La alloy powder 30%, wherein the particle size of the Ti powder is 50 μm, the particle size of the Al-60Nb alloy powder is 50 μm, the particle size of the Nb powder is 25 μm, and the particle size of the Al-20Ce-20Gd-10Y-5La alloy powder is 200 μm.

[0054] (2) Toluene is used as the ball milling medium, and the volume ratio of the ball milling medium to the powder is 4:1. The Ti powder, the Al-60Nb alloy powder, the Nb powder and the Al-20Ce-20Gd-10Y-5La alloy powder are mixed by using a planetary ball mill, the rotating speed is 150 r / min, and the time is 150 min.

[0055] (3) The powder obtained in step (2) is dried and then put into a tractor clutch friction plate mold for cold isostatic pressing, the forming pressure is 250 MPa, and the pressure maintaining time is 40 min.

[0056] (4) The tractor clutch friction plate blank obtained in step (3) is put into a sintering furnace for programmed temperature rising, the vacuum degree in the furnace is reduced to 3×10 -3 Pa, after the Ar gas flow rate is kept at a constant value of 250 mL / min, the compact is first heated from room temperature to 650℃ at a heating rate of 35℃ / min; 5

[0057] The first heated compact is second heated to 950℃ at a heating rate of 8℃ / min in the flowing Ar atmosphere;

[0058] The second heated compact is third heated to 1460℃ at a heating rate of 3℃ / min in the flowing Ar atmosphere;

[0059] The temperature is kept at 1460℃ for 5 h, and the furnace is cooled.

[0060] The tractor clutch friction plate sintered compact is processed by using precision turning, and finally the tractor clutch friction plate is obtained.

[0061] ​The Rockwell hardness of the friction plate obtained in Example 2 is 58HRC. The friction coefficient and wear rate of the alloy are tested by using a friction and wear tester. The friction pair uses a Si3N4 ball with a diameter of 9.525mm. The load is 2N. The sliding speed is 7.4cm / s. The test time is 20min. The room temperature friction coefficient of the obtained alloy is 0.70. The room temperature wear rate is 1.52x10 –4 mm 3 ·m –1 ·N –1 . The fracture toughness of the alloy is 5.08MPa·m 1 / 2 .

[0062] Example 3

[0063] The alloy composition is Ti-16.6Al-26Nb-5.6Ce-5.6Gd-2.8Y-1.4La (mass fraction, %).

[0064] (1) Ti powder, Al-60Nb (mass fraction, %) intermediate alloy powder, Nb powder and Al-20Ce-20Gd-10Y-5La (mass fraction, %) alloy powder are weighed according to the proportion. The mass percentage is: Ti powder 42%, Al-60Nb alloy powder 10%, Nb powder 20%, and Al-20Ce-20Gd-10Y-5La alloy powder 28%. The particle size of the Ti powder is 25μm. The particle size of the Al-60Nb alloy powder is 25μm. The particle size of the Nb powder is 5μm. The particle size of the Al-20Ce-20Gd-10Y-5La alloy powder is 25μm.

[0065] (2) Polyethylene glycol is used as the ball milling medium. The volume ratio of the ball milling medium to the powder is 1:1. A planetary ball mill is used to mix the Ti powder, Al-60Nb alloy powder, Nb powder and Al-20Ce-20Gd-10Y-5La alloy powder thoroughly. The rotation speed is 100r / min. The time is 200min.

[0066] (3) The powder obtained in step (2) is dried and then put into a tractor clutch friction plate mold for cold isostatic pressing. The forming pressure is 300MPa. The pressure holding time is 10min.

[0067] (4) The tractor clutch friction plate blank obtained in step (3) is put into a sintering furnace for programmed temperature rising. The vacuum degree in the furnace is reduced to 4x10 -3 Pa. After the Ar gas pressure in the furnace is stabilized at 1x10 5 Pa, the Ar gas flow rate is kept at a constant value of 350mL / min. The compact is first heated from room temperature to 700℃ at a heating rate of 40℃ / min.

[0068] The first temperature-increased compact is secondly increased in temperature to 1100℃ at a temperature increasing rate of 6℃ / min in the flowing Ar atmosphere;

[0069] The second temperature-increased compact is thirdly increased in temperature to 1500℃ at a temperature increasing rate of 2℃ / min in the flowing Ar atmosphere;

[0070] The temperature is kept at 1500℃ for 4h, and the furnace is cooled down.

[0071] The sintered compact of the tractor clutch friction plate is processed by precision turning, and the tractor clutch friction plate is finally obtained.

[0072] The high temperature tensile strength of the tractor clutch friction plate material obtained in Example 3 is >500MPa, as shown in the tensile stress-strain curve at 600℃ in the middle. Figure 2 The Rockwell hardness of the obtained friction plate is 65HRC, the friction coefficient and wear rate of the alloy are tested by using a friction and wear tester, the friction pair uses a Si3N4 ball with a diameter of 9.525mm, the load is 2N, the sliding speed is 7.4cm / s, the test time is 20min, the room temperature friction coefficient of the obtained alloy is 0.59, and the room temperature wear rate is 7.14×10 –5 mm 3 ·m –1 ·N –1 The fracture toughness of the alloy is 5.60MPa·m 1 / 2 .

[0073] The above only describes the preferred embodiments of the present application, and does not limit the present application in any form. It should be noted that for ordinary skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, and these improvements and refinements should be considered as the protection scope of the present application.

Claims

1. A titanium-aluminum-niobium alloy friction plate, characterized by, The alloy comprises the following elements in the following mass percentages: Al 8.5-25.5%, Nb 16-38%, Ce 2-6%, Gd 2-6%, Y 1-3%, La 0.5-1.5%, and the balance being Ti.

2. The method of claim 1, wherein the titanium-aluminum-niobium alloy friction plate is prepared by the steps of: The method comprises the following steps: ​ Ti powder, Al-60Nb alloy powder, Nb powder and Al-20Ce-20Gd-10Y-5La alloy powder are mixed and ball milled to obtain a mixed powder; the mass percentages of the Ti powder, the Al-60Nb alloy powder, the Nb powder and the Al-20Ce-20Gd-10Y-5La alloy powder in the mixed powder are 20-70%, 10-30%, 10-20% and 10-30% respectively; The mixed powder is cold isostatic pressed to obtain a formed material; The formed material is subjected to normal pressure programmed sintering, which comprises the following steps: the formed material is heated from room temperature to a first temperature at a first heating rate, then heated from the first temperature to a second temperature at a second heating rate, and then heated from the second temperature to a third temperature at a third heating rate, and cooled after holding at the third temperature to obtain a titanium-aluminum-niobium alloy friction plate; the first heating rate, the second heating rate and the third heating rate are 20-40 ℃ / min, 5-10 ℃ / min and 1-5 ℃ / min respectively, and the first temperature, the second temperature and the third temperature are 600-700 ℃, 950-1100 ℃ and 1400-1500 ℃ respectively.

3. The production method according to claim 2, characterized by, The particle size of the Ti powder is 20-50 μm, the particle size of the Al-60Nb alloy powder is 20-75 μm, the particle size of the Nb powder is 5-25 μm, and the particle size of the Al-20Ce-20Gd-10Y-5La alloy powder is 20-200 μm.

4. The production method according to claim 2, characterized by, The ball milling medium is polyethylene glycol or toluene, and the volume ratio of the ball milling medium to the mixed powder is (1-5):

1.

5. The production method according to claim 2 or 4, characterized by, The rotation speed of the ball milling is 100-200 r / min, and the time is 60-240 min.

6. The preparation method according to claim 2, characterized in that, The pressure of the cold isostatic pressing is 150-400 MPa, and the pressure holding time is 10-60 min.

7. The preparation method according to claim 2, characterized in that, The protective atmosphere is Ar gas, and the flow rate of the Ar gas is 100-400 mL / min.

8. The method of claim 2, wherein, The holding time is 4-8 h.

9. The preparation method according to claim 2, characterized in that, The cooling is furnace cooling.

10. Use of the titanium-aluminum-niobium alloy friction plate of claim 1 or the titanium-aluminum-niobium alloy friction plate prepared by the method of any one of claims 2-9 in a vehicle clutch.

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