阅读说明：本技术 一种碳纳米葱润滑相Ti(C,N)基自润滑复合材料及其制备方法 (Carbon nano onion lubricating phase Ti (C, N) based self-lubricating composite material and preparation method thereof ) 是由 邹芹 李艳国 卢晓乾 焦子剑 代利峰 娄志超 王志伟 赵亮 陈伟东 于 2019-10-08 设计创作，主要内容包括：本发明提供了一种碳纳米葱润滑相Ti(C,N)基自润滑复合材料及其制备方法,属于复合材料技术领域。该复合材料其按重量分数计包括：OLC 10～20％,TiN<Sub>x</Sub> 80～90％,其中,TiC<Sub>x</Sub>中的<Sub>X</Sub>为0.4≤x≤0.9或x＝1.1～1.3。这种自润滑复合材料,通过将机械合金化法制备的非化学计量比的TiNx与OLC粉末进行混合,采用热压烧结制备OLC润滑相Ti(C,N)基自润滑复合材料,利用TiNx中的空位能降低烧结温度,促进烧结。在此基础上和OLC复合烧结形成OLC润滑相Ti(C,N)基自润滑复合材料,克服传统润滑材料在极端条件下润滑失效的缺点,同时提高其硬度及断裂韧性。(The invention provides a carbon nano onion lubricating phase Ti (C, N) based self-lubricating composite material and a preparation method thereof, belonging to the technical field of composite materials. The composite material comprises the following components in parts by weight: 10-20% of OLC and TiN x 80-90%, wherein, TiC x In (1) X X is not less than 0.4 and not more than 0.9 or x is 1.1-1.3. The self-lubricating composite material is prepared by mixing TiNx prepared by a mechanical alloying method in a non-stoichiometric ratio with OLC powder, preparing an OLC lubricating phase Ti (C, N) based self-lubricating composite material by hot-pressing sintering, and utilizing the vacancy in the TiNx to reduce the sintering temperature and promote the sintering. On the basis, the OLC lubricating phase Ti (C, N) base self-lubricating composite material is formed by composite sintering with OLC, the defect that the traditional lubricating material fails in lubrication under extreme conditions is overcome, and the hardness and the fracture toughness of the traditional lubricating material are improved。)

1. A carbon nano onion lubricating phase Ti (C, N) -based self-lubricating composite material is characterized by comprising the following components in parts by weight: 10-20% of OLC and TiN_x80-90%, wherein, TiC_xIn (1)_XX is not less than 0.4 and not more than 0.9 or x is 1.1-1.3.

2. The carbon nano-onion lubricating phase Ti (C, N) -based self-lubricating composite material as claimed in claim 1, wherein the OLC has a particle size of about 2 to 10nm, and the TiN is TiN_xHas a particle size of 50nm to be fine.

3. A method for preparing a carbon nano-onion lubricating phase Ti (C, N) -based self-lubricating composite material according to claim 1 or 2, characterized in that it comprises:

annealing the detonation nano-diamond powder with the vacuum degree of 1-1.0 multiplied by 10^-2Pa, annealing temperature is 900-1800 ℃, and heat preservation is carried out for 0-2 h to prepare OLC with the particle size of about 5 nm;

performing ball milling and mixing on OLC and the raw materials according to the weight percentage, wherein the mass ratio of balls to the raw materials is 5-10: 1, the ball milling rotating speed is 250-350 r/min, the ball milling lasts for 4-8 h, each rotation lasts for 20-40min, stopping the machine for 10-20min, and performing heat dissipation to obtain OLC-TiN_xMixing;

subjecting the OLC-TiN to_xAnd carrying out hot-pressing sintering on the mixture, wherein the sintering pressure is 20-40 MPa, the sintering temperature is 1100-1800 ℃, the heat preservation time is 10-60 min, and the mixture is cooled along with the furnace.

4. The method for preparing a carbon nano-onion lubricating phase Ti (C, N) -based self-lubricating composite material according to claim 3, wherein the nano-diamond powder has an average grain size of 3 to 7nm and a purity of more than 98%.

5. The method for preparing carbon nano-onion lubricating phase Ti (C, N) -based self-lubricating composite material according to claim 3, wherein the TiC is_XThe preparation method comprises the following steps:

mixing urea and titanium powder according to a preset molar ratio, adding a dispersing agent, performing ball milling and mixing, wherein the ball-material ratio is 10-20: 1, the rotating speed is 300-600 r/min, the ball milling time is 20-80 h, and then performing vacuum annealing treatment on the obtained mixed powder, wherein the vacuum degree is 1Pa, the temperature is 500-600 ℃, and the temperature is kept for 10-30 min.

6. The method for preparing a carbon nano-onion lubricating phase Ti (C, N) -based self-lubricating composite material as claimed in claim 5, wherein the dispersant is water or ethanol, and the amount of the dispersant added is 0.2-0.5 mL per 10g of the mixed powder.

7. The method for preparing a carbon nano-onion lubricating phase Ti (C, N) -based self-lubricating composite material as claimed in claim 5, wherein the titanium powder has a particle size of 1-30 μm and a purity of more than 99%.

8. The preparation method of the carbon nano-onion lubricating phase Ti (C, N) -based self-lubricating composite material as claimed in claim 5, wherein the ball milling process adopts two kinds of WC hard alloy balls of 5mm and 8mm, and the mass ratio of the WC hard alloy balls is 7: 3.

9. The method for preparing a carbon nano-onion lubricating phase Ti (C, N) -based self-lubricating composite material as set forth in claim 5, wherein the hot press sintering comprises: for the OLC-TiN_xSlowly applying pressure to the mixture to 20-40 Mpa, vacuumizing the cavity until the vacuum degree reaches 10-40 Pa, then heating from room temperature to 560-580 ℃ at a heating rate of 130-140 ℃/min, heating to 600-620 ℃ at a heating rate of 5-10 ℃/min, preserving heat for 10min, then heating to 1000 ℃ at a heating rate of 80-120 ℃/min, and preserving heat for 10min at 1000 ℃; and then raising the temperature to 1100-1800 ℃ at a temperature raising rate of 50-100 ℃/min, and preserving the temperature for 10-60 min. And cooling along with the furnace to obtain a blank, and carrying out surface grinding and deburring treatment on the blank to obtain the OLC lubricating phase Ti (C, N) base self-lubricating composite material.

Technical Field

The invention relates to the technical field of composite materials, and relates to a carbon nano onion lubricating phase Ti (C, N) based self-lubricating composite material and a preparation method thereof.

Background

Working parts of aerospace instruments are mostly in extreme environments such as ultra-high and ultra-low temperature, vacuum, high speed, corrosive media and the like, and under the extreme working conditions, conventional lubricants are easy to evaporate to cause failure of a lubricating mechanism; the plastic-based solid self-lubricating composite material is only suitable for being used under the conditions of low speed, low load and low temperature; the metal-based self-lubricating composite material has excellent mechanical properties of base metal, but cannot cope with extreme conditions such as high and low temperature heavy load, radiation, special medium corrosion, thermal shock impact and the like; the super alloy material, such as Ni-based and Co-based composite material, is expensive in manufacturing cost and cannot be popularized on a large scale, so that the research on the self-lubricating composite material suitable for the extreme working condition of the outer space has practical significance.

And wrinkling is utilized to prepare the silicon nitride-based nano composite ceramic tool by taking nano TiN powder as a second phase additive, the fracture toughness, the Vickers hardness and the bending strength of the silicon nitride-based nano composite ceramic tool are respectively 9.1 MPa-m 1/2, 15.47GPa and 1079.8MPa, and the nano TiN is provided to reduce the sintering temperature, improve the sintering activity of powder and improve the mechanical property and mechanical property.

The research on the interfacial diffusion behavior and the strengthening and toughening of the TiN0.3 and the insoluble compound of the Gelina shows that the diffusion phenomenon exists between two phases, and the introduction of the TiN0.3 into the refractory compound improves the mechanical property, particularly the fracture toughness.

Wang L et Al sintered silicon nitride ceramics (nitrogen) and 0.2 wt% FeSi2 mixed powder at 1780 deg.C for 2h, and added Al2O3 and Y2O3 to promote sintering and toughening, to obtain high-strength and high-toughness sintered body, the fracture toughness and bending strength respectively reach 9.8 + -0.5 MPa.m 1/2 and 1086 + -48 MPa.

Disclosure of Invention

The invention aims to provide a carbon nano onion lubricating phase Ti (C, N) based self-lubricating composite material and a preparation method thereof, and the self-lubricating composite material can overcome the defect of lubrication failure of the traditional lubricating material under extreme conditions and simultaneously improve the hardness and fracture toughness of the traditional lubricating material.

In order to achieve the above purpose of the present invention, the following technical solutions are adopted:

a carbon nano onion lubricating phase Ti (C, N) based self-lubricating composite material comprises the following components in parts by weight: 10-20% of OLC and TiN_x80-90%, wherein, TiC_xIn (1)_XX is not less than 0.4 and not more than 0.9 or x is 1.1-1.3.

Further, in a preferred embodiment of the present invention, the OLC has a particle size of about 2-10nm, and the TiN is present_xHas a particle size of 50nm to be fine.

A preparation method of the carbon nano-onion lubricating phase Ti (C, N) based self-lubricating composite material comprises the following steps:

annealing the detonation nano-diamond powder with the vacuum degree of 1-1.0 multiplied by 10^-2Pa, annealing temperature is 900-1800 ℃, and heat preservation is carried out for 0-2 h to prepare OLC with the particle size of about 5 nm;

performing ball milling and mixing on OLC and the raw materials according to the weight percentage, wherein the mass ratio of balls to the raw materials is 5-10: 1, the ball milling rotating speed is 250-350 r/min, the ball milling lasts for 4-8 h, each rotation lasts for 20-40min, stopping the machine for 10-20min, and performing heat dissipation to obtain OLC-TiN_xMixing;

subjecting the OLC-TiN to_xAnd carrying out hot-pressing sintering on the mixture, wherein the sintering pressure is 20-40 MPa, the sintering temperature is 1100-1800 ℃, the heat preservation time is 10-60 min, and the mixture is cooled along with the furnace.

Further, in a preferred embodiment of the present invention, the nanodiamond powder has an average grain size of 3-7nm and a purity of more than 98%.

Further, in the preferred embodiment of the present invention, the TiC_XThe preparation method comprises the following steps:

mixing urea and titanium powder according to a preset molar ratio, adding a dispersing agent, performing ball milling and mixing, wherein the ball-material ratio is 10-20: 1, the rotating speed is 300-600 r/min, the ball milling time is 20-80 h, and then performing vacuum annealing treatment on the obtained mixed powder, wherein the vacuum degree is 1Pa, the temperature is 500-600 ℃, and the temperature is kept for 10-30 min.

Further, in a preferred embodiment of the present invention, the dispersant is water or ethanol, and the amount of the dispersant added is 0.2 to 0.5mL per 10g of the mixed powder.

Further, in a preferred embodiment of the present invention, the titanium powder has a particle size of 1 to 30 μm and a purity of more than 99%.

Further, in the preferred embodiment of the present invention, the ball milling process adopts two kinds of WC cemented carbide balls of 5mm and 8mm, and the mass ratio of the WC cemented carbide balls is 7: 3.

Further, in a preferred embodiment of the present invention, the hot press sintering includes: for the OLC-TiN_xSlowly applying pressure to the mixture to 20-40 Mpa, vacuumizing the cavity until the vacuum degree reaches 10-40 Pa, then heating from room temperature to 560-580 ℃ at a heating rate of 130-140 ℃/min, heating to 600-620 ℃ at a heating rate of 5-10 ℃/min, preserving heat for 10min, then heating to 1000 ℃ at a heating rate of 80-120 ℃/min, and preserving heat for 10min at 1000 ℃; and then raising the temperature to 1100-1800 ℃ at a temperature raising rate of 50-100 ℃/min, and preserving the temperature for 10-60 min. And cooling along with the furnace to obtain a blank, and carrying out surface grinding and deburring treatment on the blank to obtain the OLC lubricating phase Ti (C, N) base self-lubricating composite material.

Compared with the prior art, the invention has the beneficial effects that:

the invention provides a carbon nano onion lubricating phase Ti (C, N) based self-lubricating composite material, which is prepared by mixing non-stoichiometric TiNx prepared by a mechanical alloying Method (MA) with OLC powder and then sintering. Wherein, the non-stoichiometric ratio TiC_XThe ceramic allows a large number of chemical vacancies to exist on the premise of keeping the structure relatively stable, not only keeps the original excellent intrinsic characteristics of TiC ceramic with normal stoichiometric ratio, but also has good surface activity and wettability. Meanwhile, the OLC is adopted as a lubricating phase,

the lubricating grease not only is resistant to acid and alkali corrosion and high in oxidation temperature, but also has small cutting effect on a matrix, small stress concentration effect and small influence on toughness reduction of the matrix, and can play a good lubricating effect. OLC can generate graphite fragments, amorphous carbon and even diamond-like carbon coating (DLC) in the friction process, and further enrich the lubricating mechanism; the diamond core in OLC can act as a hard phase, enhancing the wear resistance of the matrix.

The OLC lubricating phase Ti (C, N) base self-lubricating composite material is prepared by hot-pressing sintering, the sintering temperature can be reduced by utilizing vacancies in TiNx, sintering is promoted, and the OLC lubricating phase Ti (C, N) base self-lubricating composite material is formed by OLC composite sintering on the basis, so that the defect of lubrication failure of the traditional lubricating material under extreme conditions is overcome, and meanwhile, the hardness and the fracture toughness of the traditional lubricating material are improved.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to examples, but it will be understood by those skilled in the art that the following examples are only illustrative of the present invention and should not be construed as limiting the scope of the present invention. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

The embodiment provides a carbon nano-onion lubricating phase Ti (C, N) based self-lubricating composite material, which comprises the following components in parts by weight: OLC 10-20%, TiN_x80-90%, wherein, TiC_xIn (1)_XX is not less than 0.4 and not more than 0.9 or x is 1.1-1.3.

Further, in the preferred embodiment of the present invention, OLC has a particle size of about 2-10nm, TiN_xHas a particle size of 50nm to be fine. The raw materials with the grain diameter are adopted for sintering, so that the sintering performance is good, and the mechanical properties such as hardness, toughness and the like are better.

The preparation method of the carbon nano-onion lubricating phase Ti (C, N) based self-lubricating composite material comprises the following steps:

step S1, annealing the detonation nano-diamond powder with the vacuum degree of 1-1.0 multiplied by 10^-2Pa, annealing temperature of 900-1800 ℃, and heat preservation for 0-2 h to prepare the particlesOLC with a diameter of about 5 nm.

Further, in a preferred embodiment of the present invention, the nanodiamond powder has an average grain size of 3-7nm and a purity of greater than 98%.

Step S2: mixing OLC and TiN by weight percentage_xBall milling and mixing are carried out, the mass ratio of balls to materials is 5-10: 1, the ball milling rotating speed is 250-350 r/min, the ball milling is carried out for 4-8 h, 20-40min per rotation is carried out, the machine is stopped for 10-20min, and heat dissipation is carried out to obtain OLC-TiN_xMixing;

mixing OLC and TiN by ball milling_xAnd in the process of mixing materials, two components in the matrix are diffused mutually through mechanical alloying action to form the matrix with higher activity.

Further, in a preferred embodiment of the present invention, TiC_XThe preparation method comprises the following steps:

mixing urea and titanium powder according to a preset molar ratio, adding a dispersing agent, performing ball milling and mixing, wherein the ball-material ratio is 10-20: 1, the rotating speed is 300-600 r/min, the ball milling time is 20-80 h, and then performing vacuum annealing treatment on the obtained mixed powder, wherein the vacuum degree is 1Pa, the temperature is 500-600 ℃, and the temperature is kept for 10-30 min.

Wherein, TiC is prepared_XThe raw materials and the mass ratio thereof are shown in Table 1, TiC is prepared_X(x is more than or equal to 0.4 and less than or equal to 0.9 or x is 1.1-1.3), urea and titanium powder are used as raw materials.

TABLE 1 preparation of TiN_xThe raw materials and the mass ratio thereof

Further, in a preferred embodiment of the present invention, the dispersant is water or ethanol, and the amount of the dispersant added is 0.2 to 0.5mL per 10g of the mixed powder.

Further, in the preferred embodiment of the present invention, the titanium powder has a particle size of 1-30 μm and a purity of more than 99%.

Further, in the preferred embodiment of the present invention, the ball milling process adopts two kinds of WC hard alloy balls of 5mm and 8mm, and the mass ratio of the WC hard alloy balls is 7: 3. The ball milling is carried out by adopting two grinding balls with different diameters, so that the powder can be mixed more uniformly, and the mechanical alloying effect is better.

Step S3: OLC-TiN_xAnd carrying out hot-pressing sintering on the mixture, wherein the sintering pressure is 20-40 MPa, the sintering temperature is 1100-1800 ℃, the heat preservation time is 10-60 min, and the mixture is cooled along with the furnace.

Compared with SPS sintering technology, the composite material prepared by hot-pressing sintering technology has stronger mechanical property and can be more suitable for engineering application.

Further, in a preferred embodiment of the present invention, the hot press sintering comprises: for OLC-TiN_xSlowly applying pressure to the mixture to 20-40 Mpa, vacuumizing the cavity until the vacuum degree reaches 10-40 Pa, then heating from room temperature to 560-580 ℃ at a heating rate of 130-140 ℃/min, heating to 600-620 ℃ at a heating rate of 5-10 ℃/min, preserving heat for 10min, then heating to 1000 ℃ at a heating rate of 80-120 ℃/min, and preserving heat for 10min at 1000 ℃; and then raising the temperature to 1100-1800 ℃ at a temperature raising rate of 50-100 ℃/min, and preserving the temperature for 10-60 min. Cooling along with the furnace to obtain a blank, and carrying out surface grinding and deburring treatment on the blank to obtain the OLC lubricating phase Ti (C, N) base self-lubricating composite material.

The features and properties of the present invention are further described in detail below with reference to examples: