CN105603234A - Preparation method of mica powder containing titanium-aluminum-based self-repairing composite - Google Patents

Abstract

The invention provides a preparation method of a titanium-aluminum base self-repairing composite material containing mica powder. The method comprises the following steps: 1) according to the molar ratio of Ti:Al:Nb:Cr:B=48:47:2:2:1, take Ti powder, Al powder, Nb powder, Cr powder and B powder, press The amount of mica powder added is 5-10wt.% of the total mass, and the mica powder is weighed; 2) the composite material matrix powder is mixed with the mica powder; 3) the above-mentioned mixture is wet-milled, sieved, and cleaned to obtain a mixed suspension solution, then filter to remove the filtrate, and vacuum dry to obtain the pretreated mixed powder; 4) place the pretreated mixed powder in a graphite mold, and then adopt a discharge plasma sintering method under vacuum conditions, that is, sinter to obtain the mica-containing powder Titanium-aluminum based self-healing composites. The composite material prepared by the method has good comprehensive properties, excellent tribological properties and self-repairing properties, and the method has simple process, easy control of process parameters, low cost and short preparation cycle.

Description

A preparation method of titanium-aluminum matrix self-repairing composite material containing mica powder

technical field

The invention relates to the technical field of metal-based composite material preparation, in particular to a preparation method of a titanium-aluminum-based self-repairing composite material containing mica powder.

Background technique

Titanium-aluminum alloy has low density, high specific strength, large specific modulus, good oxidation resistance, good creep resistance, and better room temperature toughness than ceramic materials. These excellent properties make it an ideal lightweight structural material with broad application prospects in advanced fields such as aerospace and high-temperature engines ([1] Feng Xudong, Yuan Qinglong, Cao Jingjing, Su Zhijun. Research progress on TiAl-based alloys[J]. Aerospace Manufacturing Technology, 2009 (3): 35-38; [2] Qu Xuanhui, Huang Boyun, Lu Haibo, etc. A review of TiAl ordered alloy research [J]. Rare Metal Materials and Engineering, 1991, (4): 3- 14.).

With the development of modern machinery and equipment in the direction of high power, high heat load, high pressure and long service life, wear self-repair technology has become one of the main development directions of equipment maintenance engineering, and it is also a frontier research content in the field of tribology. The use of wear self-repair technology can make parts realize self-organization, self-adaptation and self-repair functions during the friction process, so as to increase lubrication and reduce friction and wear. This new type of lubricating material can not only form an easy-to-shear film on the friction surface, reduce the friction factor, and directly adsorb to the scratches or micro-pits of the parts for self-healing, but also help reduce friction vibration and reduce noise. Save energy, realize the repair of the geometry of the friction surface of the part and the optimization of the fit clearance. Therefore, it is necessary to develop more new self-healing composite materials with self-healing function.

Contents of the invention

The object of the present invention is to provide a method for preparing a titanium-aluminum matrix self-repairing composite material containing mica powder. The composite material prepared by the method has excellent self-repairing performance and tribological performance, and the method has a simple process and easy control of process parameters.

The technical scheme that the present invention takes for solving the problems of the technologies described above is:

A kind of preparation method that contains mica powder titanium-aluminum matrix self-repairing composite material, it comprises the steps:

1) Ingredients: according to the molar ratio of Ti:Al:Nb:Cr:B = 48:47:2:2:1, weigh Ti powder, Al powder, Nb powder, Cr powder, B powder, according to the amount of mica powder added 5-10wt.% of the total mass of Ti powder, Al powder, Nb powder, Cr powder, B powder and mica powder, weighing mica powder;

2) Mixing: mix Ti powder, Al powder, Nb powder, Cr powder, B powder and mica powder;

3) Pretreatment: wet grinding the above mixed materials, sieving, and washing to obtain a mixed suspension solution, then filtering to remove the filtrate, and vacuum drying to obtain a pretreated mixed powder;

4) Sintering: placing the pretreated mixed powder in a graphite mold, and then adopting a discharge plasma sintering method under vacuum conditions to obtain the titanium-aluminum-based self-repairing composite material containing mica powder.

In the above scheme, the wet milling step in step 3) is to put the mixed material, alcohol and steel balls in a stainless steel vacuum ball mill tank, and wet mill in a ball mill, and the wet milling time is 3-4 hours.

In the above scheme, the rotational speed of the ball mill is 200-300r/min, and the mass ratio of the ball to material is 10:1.

In the above scheme, the vacuum degree in the stainless steel vacuum ball mill tank is 10-20Pa.

In the above scheme, the sieving step in step 3) is to sieve through a 300-mesh stainless steel sieve.

In the above solution, the vacuum degree of vacuum drying in step 3) is 0.011-0.021 MPa, the drying temperature is 60-80° C., and the drying time is 5-6 hours.

In the above scheme, the inner diameter of the graphite mold in the step 4) is 20mm.

In the above scheme, the spark plasma sintering process is as follows: the sintering temperature is 1000-1050°C, the heating rate is 100-200°C/min, the sintering pressure is 40-50MPa, and the vacuum degree is 1×10 ^-2 -1×10 ^-1 Pa, holding time is 3-6min.

The beneficial effects of the present invention are:

1. Fast preparation and high feasibility: During the preparation process, SPS is used to sinter the material, the reaction cycle is short, the process parameters are stable, and the composite material can be prepared quickly, and the composite material has high purity, wide temperature range response, excellent Comprehensive performance and other characteristics, and suitable for large-scale mass production.

2. The preparation process has few technological steps and requires simple equipment: it has the characteristics of wide source of raw materials, low price, simple process and easy control.

3. On the basis of avoiding surface pollution and oxidation of TiAl-based composite material particles, SPS is used to prepare mica powder-containing TiAl-based composite materials with high density and excellent comprehensive properties, which can reduce the sintering temperature and shorten the sintering time, such as synthesis temperature Low temperature of 1000-1050℃, short synthesis time of 3-6min, saving energy and reducing synthesis cost.

4. The titanium-aluminum matrix composite material containing mica powder prepared in the present invention is a new type of self-repairing composite material. It is a high-performance self-healing composite material designed with TiAl as the matrix and mica powder as the repair phase.

5. The titanium-aluminum-based self-repairing composite material containing mica powder prepared by the present invention has good self-repairing performance and tribological performance.

6. The composite material prepared by the present invention contains repairing additive phase mica powder, exhibits a good repairing effect, improves the anti-friction and wear-resistant properties of the material, and is easy to process and prepare.

Description of drawings

Fig. 1 is the preparation process flowchart of the present invention.

Fig. 2 is an electron probe photo of the wear scar surface of the titanium-aluminum-based self-healing composite material containing mica powder prepared in Example 1 of the present invention at a temperature of 25°C.

Fig. 3 is an electron probe photo of the wear scar surface of the titanium-aluminum-based self-healing composite material containing mica powder prepared in Example 1 of the present invention at a temperature of 200°C.

Fig. 4 is an electron probe photo of the wear scar surface of the titanium-aluminum-based self-healing composite material containing mica powder prepared in Example 1 of the present invention at a temperature of 400°C.

Fig. 5 is an electron probe photo of the wear scar surface of the titanium-aluminum-based self-healing composite material containing mica powder prepared in Example 1 of the present invention at a temperature of 600°C.

Fig. 6 is the friction coefficient and wear rate curves of the mica powder-containing titanium-aluminum matrix self-repairing composite material prepared in Example 1 of the present invention at different temperatures. The test conditions are: sliding frequency 10Hz, time 40min, friction radius 3mm, load 12N. The HT-1000 high-temperature friction and wear testing machine is used, according to the American standard ASTMG99-95, and the friction pair is an Al ₂ O ₃ ball with a diameter of 6mm (HV20.5GPa, Ra0.01μm).

Fig. 7 is a dynamic friction coefficient curve of the titanium-aluminum-based self-healing composite material containing mica powder prepared in Example 2 of the present invention at a temperature of 600°C.

Fig. 8 is an electron probe photo of the wear scar surface of the titanium-aluminum-based self-healing composite material containing mica powder prepared in Example 2 of the present invention at a temperature of 600°C.

Fig. 9 is a FESEM photo of the wear scar fracture of the titanium-aluminum-based self-healing composite material containing mica powder prepared in Example 2 of the present invention at a temperature of 600°C.

detailed description

The present invention will be further described below in conjunction with the accompanying drawings and embodiments, but the content of the present invention is not limited to the following embodiments.

Example 1:

As shown in Figure 1, a kind of preparation method of the titanium-aluminum matrix self-repairing composite material containing mica powder, it comprises the steps:

1) Using Ti powder, Al powder, Nb powder, Cr powder and B powder as the matrix raw materials, according to the molar ratio of Ti:Al:Nb:Cr:B = 48:47:2:2:1 mixed, weigh 5.6457 gram of Ti powder, 3.1157 gram of Al powder, 0.4565 gram of Nb powder, 0.2555 gram of Cr powder and 0.0266 gram of B powder, a total of 9.5 grams, then add 0.5 gram of mica powder to the above powder to obtain the batching;

2) Put the above-mentioned ingredients and steel balls in a vacuum steel ball mill jar, and wet mill them on a planetary ball mill for 3 hours under low vacuum conditions; the wet milling medium is alcohol; wherein: the speed of the ball mill is 200r/min, and the mass ratio of balls to materials is 10:1, vacuum degree 10Pa;

3) After ball milling, the mixed slurry containing steel balls is sieved and cleaned through a 300-mesh stainless steel sieve to obtain a mixed suspension solution. After the mixed suspension solution is filtered to remove the filtrate, vacuum-dry (vacuum degree is 0.011MPa, temperature is 60°C , the time is 5 hours), to obtain the pretreated mixed powder;

4) The dried powder is placed in a graphite grinding tool with an inner diameter of 20mm, and then spark plasma sintering is carried out under vacuum conditions. Among them, the sintering temperature is 1000℃, the heating rate is 100℃/min, the sintering pressure is 40MPa, the holding time is 3min, and the vacuum degree is 1×10 ^-2 Pa. The titanium-aluminum matrix self-healing composite material containing mica powder is prepared.

The hardness of the titanium-aluminum-based self-healing composite material containing mica powder prepared in Example 1 was tested by a Vickers hardness tester, and the hardness was HV1592.2, and the actual density of the composite material was 3.71 g/cm ³ according to the drainage method. Figures 2 to 5 are electron probe photos of the wear scar surfaces of the titanium-aluminum matrix self-healing composite materials containing mica powder prepared in Example 1, corresponding to the test temperatures of 25°C, 200°C, 400°C and 600°C respectively , Fig. 2 to Fig. 5 show that there are no deep furrows and peeling pits on the wear scar surface of the composite material, which can ensure that it has good tribological properties in the temperature range of 25-600 ° C, which also shows that the composite material Has good self-healing properties. In addition, the wear rate of the sample can be calculated by formula (1) (MYNiu, QLBi, J. Yang, WMLiu. Tribological performance of a Ni ₃ Almatrix self-lubricating composite coating tested from 25 to 1000 ° C. Surf Coat Technol, 2012, 206 (19-20): 3938-3943.):

W=V/PS=Vρ _w /PSρ _w =M _w /PSρ _w (1)

In the formula: V represents the wear volume, P represents the load, S represents the sliding distance, ρ _w represents the material density, M _w represents the mass of the worn material, and the unit of W is mm ³ (Nm) ^-1 .

Fig. 6 is the friction coefficient and wear rate curve of the titanium-aluminum matrix self-repairing composite material containing mica powder obtained in Example 1 of the present invention at different temperatures, and Fig. 6 illustrates the friction coefficient and wear rate of the composite material at a temperature of 25 ° C. The wear rate is 0.47 and 5.31×10 ^-4 mm ³ /(Nm), the friction coefficient and wear rate at 200°C are 0.38 and 7.5×10 ^-4 mm ³ /(Nm), and the friction coefficient and wear rate at 400°C 0.33 and 6.24×10 ^-4 mm ³ /(Nm), respectively, and the friction coefficient and wear rate at 600°C are 0.28 and 4.2×10 ^-4 mm ³ /(Nm), respectively. Excellent tribological properties. With the increase of temperature, the friction coefficient and wear rate are in a downward trend as a whole.

Example 2:

1) Using Ti powder, Al powder, Nb powder, Cr powder and B powder as the matrix raw materials, mix according to the molar ratio of Ti:Al:Nb:Cr:B=48:47:2:2:1, weigh 5.3485 gram of Ti powder, 2.9517 gram of Al powder, 0.4325 gram of Nb powder, 0.2421 gram of Cr powder and 0.0252 gram of B powder, a total of 9 grams, then add 1 gram of mica powder to the above powder to obtain the batching;

2) Put the above-mentioned ingredients and steel balls in a vacuum steel ball mill tank, and wet mill them on a planetary ball mill for 6 hours under low vacuum conditions; the wet mill medium is alcohol; wherein: the speed of the ball mill is 300r/min, and the ball-to-material mass ratio is 10:1, vacuum degree 20Pa;

3) After ball milling, the mixed slurry containing steel balls is sieved and cleaned through a 300-mesh stainless steel sieve to obtain a mixed suspension solution. After the mixed suspension solution is filtered to remove the filtrate, vacuum-dry (vacuum degree is 0.021MPa, temperature is 80°C , the time is 6 hours), to obtain the pretreated mixed powder;

4) The dried powder is placed in a graphite grinding tool with an inner diameter of 20mm, and then spark plasma sintering is carried out under vacuum conditions. Among them, the sintering temperature is 1050℃, the heating rate is 200℃/min, the sintering pressure is 50MPa, the holding time is 6min, and the vacuum degree is 1×10 ^-1 Pa. The titanium-aluminum matrix self-healing composite material containing mica powder is prepared.

The hardness of the titanium-aluminum matrix self-healing composite material containing mica powder prepared in Example 2 was tested by a Vickers hardness tester, and the hardness was HV1559.6, and the actual density of the composite material was 3.58 g/cm ³ according to the drainage method. Figure 7 is the dynamic friction coefficient curve of the titanium-aluminum-based self-healing composite material containing mica powder prepared in Example 2 at a temperature of 600°C, indicating that the friction coefficient of the composite material is relatively stable, and the value is relatively close to 0.4. In addition, the wear rate of the composite material prepared in Example 2 was calculated according to formula (1) to be 3.38×10 ⁻⁴ mm ³ /(Nm). Therefore, the prepared composite material exhibits excellent tribological properties. Figure 8 is an electronic probe photo of the wear scar surface of the mica powder-containing titanium-aluminum matrix self-repairing composite material prepared in Example 2 at a temperature of 600 ° C, indicating that the friction and wear surface of the composite material is relatively smooth, forming a layer Relatively dense self-healing film, thus obtaining excellent tribological properties. Fig. 9 is a FESEM photo of the wear scar port of the titanium-aluminum matrix self-healing composite material containing mica powder prepared in Example 2 at a temperature of 600°C. It is clearly seen that the matrix structure is covered with a relatively flat self-healing film.

Each raw material enumerated in the present invention can realize the present invention, and the upper and lower limit value of each raw material, interval value can realize the present invention, the upper and lower limit value of process parameter (as temperature, time, vacuum degree etc.) of the present invention And interval value can realize the present invention, does not enumerate embodiment one by one here.

Claims (8)

1. containing a preparation method for the aluminium base Self-repair Composites of mica powder titanium, it is characterized in that, it comprises the steps:

1) batching: according to mol ratio=48:47:2:2:1 of Ti:Al:Nb:Cr:B, take Ti powder, Al powder, Nb powder, Cr powder,B powder, is the 5-10wt.% of Ti powder, Al powder, Nb powder, Cr powder, B powder and mica powder gross mass by mica powder addition, claimsGet mica powder;

2) batch mixing: Ti powder, Al powder, Nb powder, Cr powder, B powder are mixed with mica powder;

3) pretreatment: above-mentioned batch mixing is carried out to wet-milling, sieve, after cleaning, obtain mixing suspension solution, then remove by filter filtrate, trueThe empty dry mixed-powder that pretreatment is good that obtains;

4) sintering: the mixed-powder that pretreatment is good is placed in graphite jig, then takes discharge plasma sintering method under vacuum condition,Obtain described containing the aluminium base Self-repair Composites of mica powder titanium.

2. the preparation method containing the aluminium base Self-repair Composites of mica powder titanium as claimed in claim 1, is characterized in that described step3) the wet-milling step in is that batch mixing, alcohol and steel ball are placed in stainless-steel vacuum ball grinder, and wet-milling in ball mill, when wet-millingBetween be 3-4 hour.

3. the preparation method containing the aluminium base Self-repair Composites of mica powder titanium as claimed in claim 2, is characterized in that, ball mill turnsSpeed is 200-300r/min, and ball material mass ratio is 10:1.

4. the preparation method containing the aluminium base Self-repair Composites of mica powder titanium as claimed in claim 2, is characterized in that, described stainlessIn steel vacuum sphere grinding jar, vacuum is 10-20Pa.

5. the preparation method containing the aluminium base Self-repair Composites of mica powder titanium as claimed in claim 1, is characterized in that described step3) step of sieving in is to sieve by 300 order stainless steel sieves.

6. the preparation method containing the aluminium base Self-repair Composites of mica powder titanium as claimed in claim 1, is characterized in that described step 3)Vacuum drying vacuum be 0.011-0.021MPa, baking temperature is 60-80 DEG C, be 5-6 hour drying time.

7. the preparation method containing the aluminium base Self-repair Composites of mica powder titanium as claimed in claim 1, is characterized in that described step 4)In the interior diameter of graphite jig be 20mm.

8. the preparation method containing the aluminium base Self-repair Composites of mica powder titanium as claimed in claim 1, is characterized in that, described putsElectricity plasma sintering process is: sintering temperature is that 1000-1050 DEG C, heating rate are that 100-200 DEG C/min, sintering pressure are40-50MPa, vacuum are 1 × 10^-2-1×10^-1Pa, temperature retention time are 3-6min.