CN1317228C

CN1317228C - Ti3AlC2/Ti5Si3 compound material and its preparation method

Info

Publication number: CN1317228C
Application number: CNB200410082975XA
Authority: CN
Inventors: 周延春; 陈继新
Original assignee: Institute of Metal Research of CAS
Current assignee: Institute of Metal Research of CAS
Priority date: 2004-12-15
Filing date: 2004-12-15
Publication date: 2007-05-23
Anticipated expiration: 2024-12-15
Also published as: CN1789202A

Abstract

The present invention relates to in-situ synthesis titanium silicide (Ti5Si3) granule reinforcing aluminium titanium carbide (Ti3AlC2) base composite material and a preparation method thereof. Ti3 AlC2 /Ti5 Si3 composite material with different volume ratios is prepared by adding a certain amount of silicon, wherein the volume percentage of the titanium silicide granule reinforcing phase is from 10 to 40 %. In the concrete preparation method, firstly, titanium powder, aluminium powder, silicon powder and graphite powder are used as raw material, the molar ratio of Ti to Al to Si to C is 3: (1.1 to x): x: (1.8 to 2.0), wherein x is from 0.1 to 0.5; raw material powder is mixed with a physical mechanical method for 8 to 24 hours, and is filled into a graphite mold, and the applied pressure intensity is from 10 to 20MPa; finally, the raw material powder is sintered in a hot pressing furnace under a protective atmosphere, the rate of temperature rise is from 10 to 50 DEG C / minute, the sintering temperature is from 1400 to 1600 DEG C, the sintering time is from 0.5 to 2 hours, and the sintering pressure intensity is from 20 to 40MPa. Aluminium titanium carbide / titanium silicide composite material with high purity and high strength can be prepared with the method of the present invention at lower temperature for shorter time.

Description

A kind of aluminum titanium carbide/titanium silicide matrix material and preparation method thereof

Technical field

The present invention relates to ceramic matric composite and preparation method thereof, be specially the synthetic a kind of titanium silicide (Ti of original position ₅Si ₃) particle-reinforced aluminum titanium carbide (Ti ₃AlC ₂) based composites and preparation method thereof.

Background technology

Ti ₃AlC ₂It is a kind of novel ternary layered ceramic material.Document 1: material journal (Acta Materialia50,3141 (2002)) people such as Wang studies show that it combines the plurality of advantages of pottery and metal in, have characteristics such as low density, high-modulus, anti-thermal shock and excellent high-temperature oxidation-resistance, thereby the potential wide application prospect is all arranged at high-technology fields such as Aeronautics and Astronautics, nuclear industry, fuel cell and electronic information.

Because pure Ti ₃AlC ₂Intensity and hardness are on the low side, have limited its application as structured material.Introducing hard ceramic particles is one of effective ways that improve ternary layered ceramic intensity.As a kind of method of introducing the particle wild phase, original position is synthetic to have advantages such as phase interface cleaning, mechanical property are good; In addition, because wild phase is the original position synthetic, and prepare wild phase earlier, compare with the matrix mechanically mixing, preparation cost greatly reduces.Also there is not relevant in-situ particle to strengthen Ti at present ₃AlC ₂Report.Pertinent literature concentrates on another kind and Ti ₃AlC ₂Structure and kin ternary layered ceramic material, i.e. silicon titanium carbide (Ti ₃SiC ₂) the matrix material in-situ preparing on, as document 2: people such as Radhakrishnan has reported the Ti of in-situ preparing in the material wall bulletin (Scripta Materialia 34,1809 (1996)) ₃SiC ₂/ SiC matrix material, its hardness and fracture toughness increase; Document 3: people such as the middle Ho-Duc of alloy and compound periodical (Journal of Alloys and Compounds 350,303 (2003)) have reported that matrix is Ti ₃SiC ₂, and containing the matrix material of 30% volume parts TiC or SiC, the bending strength that its result shows two kinds of matrix materials is all than enhanced Ti not ₃SiC ₂Matrix is low, illustrates that reinforced effects is unsatisfactory.

Summary of the invention

The object of the present invention is to provide that a kind of mechanical property is good, simple to operate, easy control of process conditions, aluminum titanium carbide/titanium silicide matrix material that cost is low and preparation method thereof.

Technical scheme of the present invention is:

Original position is synthesized aluminum titanium carbide/titanium silicide matrix material, is made up of titanium silicide particle wild phase and aluminum titanium carbide matrix, and wherein the percent by volume of titanium silicide particle wild phase is 10～40%.

Described original position is synthesized the preparation method of aluminum titanium carbide/titanium silicide matrix material, is raw material with simple substance titanium valve, aluminium powder, silica flour and Graphite Powder 99, and the mol ratio of Ti: Al: Si: C is 3: (1.1-x): x: (1.8～2.0), wherein x is 0.1～0.5.Raw material powder was mixed 8～24 hours through physical mechanical method; pack into and cold pressing in the graphite jig; the pressure that applies is 10～20MPa; sintering in the hot pressing furnace that is connected with protection of inert gas atmosphere; temperature rise rate is 10～50 ℃/minute, and sintering temperature is that 1400～1600 ℃, sintering time are that 0.5～2 hour, sintering pressure are 20～40MPa.The present invention can in-situ preparing goes out to have the Ti of higher-strength ₃AlC ₂/ Ti ₅Si ₃Matrix material.

The titanium valve of described adding, aluminium powder, silica flour and Graphite Powder 99 size range are 200～400 orders; Described sintering processing is hot pressed sintering or HIP sintering; Described inert gas is argon gas, helium or neon; Described physical mechanical method is mixed into to do in the urethane ball grinder and mixes or ball milling in the alcohol medium.

Advantage of the present invention is:

1, the interface between wild phase and matrix is pure, and mechanical property is good.Adopt the inventive method can realize that original position synthesizes titanium silicide particle-reinforced aluminum titanium carbide matrix.The hardness of this matrix material, compressive strength, bending strength are all than pure Ti ₃AlC ₂Raising is by a relatively large margin arranged.Because titanium silicide (Ti ₅Si ₃) have very high fusing point (2130 ℃) and a lower density (4.32g/cm ³), thereby be suitable as very much the wild phase of aluminum titanium carbide.

2, technology is simple, and cost is low.The present invention is by adding a certain amount of elemental silicon, react with the raw material titanium, and original position is synthesized titanium silicide (Ti ₅Si ₃) particle, as wild phase, and aluminum titanium carbide (Ti ₃AlC ₂) also hot pressure reaction generation simultaneously of matrix.Owing in sintering process, there is liquid phase to occur, utilize the quick mass transfer process of liquid phase, chemical time is shortened greatly, make densification process become very easy again, thereby reduced cost.

3, aluminum titanium carbide/titanium silicide matrix material had both kept the plurality of advantages of aluminum titanium carbide matrix, as have characteristics such as low density, high-modulus, anti-thermal shock and excellent high-temperature oxidation-resistance, simultaneously improved intensity again, thereby be applicable to more as a kind of Aeronautics and Astronautics structured material.

Description of drawings

Fig. 1 is the Ti of Different Silicon add-on (x) ₃AlC ₂/ Ti ₅Si ₃The X-ray diffraction spectrum of matrix material: (a) x=0.15; (b) x=0.25; (c) x=0.35.Along with the increase of silicon add-on, Ti ₅Si ₃The content of phase also increases gradually.

Fig. 2 is Ti ₃AlC ₂/ Ti ₅Si ₃The matrix material bending strength is with the variation of silicon add-on.Along with the increase of silicon add-on, bending strength also increases gradually.

Embodiment

Below by example in detail the present invention is described in detail.

Embodiment 1

With size range is 200～400 purpose titanium valves 73.63 gram, aluminium powder 13.13 grams, silica flour 2.16 grams and graphite 11.08 grams ball milling 8 hours in ball grinder, the coldmoulding in the graphite jig of packing into afterwards, the pressure that applies is 10MPa, puts into the hot pressing furnace hot pressed sintering.Temperature rise rate is 10 ℃/minute, is heated to 1400 ℃ of insulations 2 hours, and pressure is added to 25MPa gradually simultaneously.Whole sintering process all is to carry out under argon shield.The reaction product that obtains is Ti through X-ray diffraction analysis ₃AlC ₂And Ti ₅Si ₃Two-phase is shown in Fig. 1 (a).Quantitative phase analysis shows Ti ₅Si ₃Volume content be about 12%.The Vickers' hardness of this matrix material is 3.49GPa (load is 10N), and compressive strength is 819MPa, and fracture toughness is 7.87MPam ^1/2

Embodiment 2

With size range is 200～400 purpose titanium valves 73.59 gram, aluminium powder 11.74 grams, silica flour 3.6 grams and graphite 11.07 grams ball milling 16 hours in ball grinder, the coldmoulding in the graphite jig of packing into afterwards, the pressure that applies is 15MPa, puts into the hot pressing furnace hot pressed sintering.Temperature rise rate is 20 ℃/minute, is heated to 1500 ℃ of insulations 1 hour, and pressure is added to 30MPa gradually simultaneously.Whole sintering process all is to carry out under argon shield.The reaction product that obtains is Ti through X-ray diffraction analysis ₃AlC ₂And Ti ₅Si ₃Two-phase is shown in Fig. 1 (b).Quantitative phase analysis shows Ti ₅Si ₃Volume content be about 20%.The Vickers' hardness of this matrix material is 3.79GPa, and compressive strength is 919MPa, and fracture toughness is 7.09MPam ^1/2

Embodiment 3

With size range is 200～400 purpose titanium valves, 73.55 grams, aluminium powder 10.36 grams, silica flour 5.03 grams and graphite 11.15 grams ball milling in the alcohol medium, the coldmoulding in the graphite jig of packing into afterwards, the pressure that applies is 20MPa, puts into the hot pressing furnace HIP sintering.Temperature rise rate is 50 ℃/minute, is heated to 1600 ℃ of insulations 0.5 hour, and pressure is added to 20MPa gradually simultaneously.Whole sintering process all is to carry out under argon shield.The reaction product that obtains is that x ray diffraction analysis x is Ti through X-ray diffraction analysis ₃AlC ₂And Ti ₅Si ₃Two-phase is shown in Fig. 1 (c).Quantitative phase analysis shows Ti ₅Si ₃Volume content be about 30%.The Vickers' hardness of this matrix material is 4.37GPa, and compressive strength is 966MPa, and fracture toughness is 7.96MPam ^1/2

Comparative example

The pure Ti that adopted the prepared identical with embodiment 1 ₃AlC ₂, the Vickers' hardness that records is 3.07GPa; Compressive strength is 671MPa; Fracture toughness is 8.15MPam ^1/2As seen, pure Ti ₃AlC ₂Fracture toughness and Ti ₃AlC ₂/ Ti ₅Si ₃Matrix material is suitable substantially, and hardness and compressive strength are all than pure Ti ₃AlC ₂High.Even more important is that the test result of bending strength shows that various matrix materials are all than pure Ti ₃AlC ₂Want high, as shown in Figure 2.Original position TiC that document 3 is mentioned in this and the background technology or SiC particle strengthen Ti ₃SiC ₂Situation obviously different, their result is that the bending strength of matrix material is low all the better.

By embodiment 1, embodiment 2, embodiment 3 and comparative example as seen, the Ti of present method preparation ₃AlC ₂/ Ti ₅Si ₃Matrix material has advantages such as purity height, mechanical property are good, and has realized first the in-situ particle of such ternary layered ceramic is strengthened.

Claims

1, a kind of aluminum titanium carbide/titanium silicide matrix material is characterized in that: be made up of titanium silicide particle wild phase and aluminum titanium carbide matrix, wherein the percent by volume of titanium silicide particle wild phase is 10～40%.

2; preparation method according to the described aluminum titanium carbide of claim 1/titanium silicide matrix material; it is characterized in that: by adding elemental silicon; prepare the aluminum titanium carbide/titanium silicide matrix material of different volumes ratio; with titanium valve; aluminium powder; silica flour and Graphite Powder 99 are raw material; the mol ratio of Ti: Al: Si: C is 3: (1.1-x): x: (1.8～2.0); wherein the add-on x of silicon is 0.1～0.5; raw material powder was mixed 8～24 hours through physical mechanical method; pack in the graphite jig; the pressure that applies is 10～20MPa; sintering in the hot pressing furnace that is connected with protection of inert gas atmosphere; temperature rise rate is 10～50 ℃/minute, and sintering temperature is 1400～1600 ℃; sintering time is 0.5～2 hour; sintering pressure is 20～40MPa.

3, according to the preparation method of the described aluminum titanium carbide of claim 2/titanium silicide matrix material, it is characterized in that: the titanium valve of described adding, aluminium powder, silica flour and Graphite Powder 99 size range are 200～400 orders.

4, according to the preparation method of the described aluminum titanium carbide of claim 2/titanium silicide matrix material, it is characterized in that: described sintering processing is hot pressed sintering or HIP sintering.

5, according to the preparation method of the described aluminum titanium carbide of claim 2/titanium silicide matrix material, it is characterized in that: described rare gas element is argon gas, helium or neon.

6, according to the preparation method of the described aluminum titanium carbide of claim 2/titanium silicide matrix material, it is characterized in that: described physical mechanical method mixes to adopt to be done mixed in the urethane jar or ball milling in the alcohol medium.