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Ternary compounds of silicon carbide, titanium (Ti 3 SiC 2 ) is a new type of ceramic material, the theoretical density of 4.53 g / cm 3 , melting point More than 3000 ℃, caused widespread concern because of its dual character of both metal and ceramic. It like a metal having good thermal and electrical conductivity, and not sensitive to thermal shock, high temperature performance of plastic behavior, but also the same as the ceramic has a high melting point, high yield strength, resistance to corrosion, oxidation, and other properties, is considered as a high temperature The new type of ceramic material is one of the most promising structural materials and electrode materials. In this paper, pressureless sintering preparation of high purity Ti 3 the SiC 2 ceramic materials, its as reinforcing phase in the Cu matrix composites do explore and pressureless sintering and spark plasma sintering technology to prepare (1-x) Ti 3 SiC 2 -xSiC (x = 0-1) composites, on this basis, by spark plasma sintering Ti, Mo, W / Ti 3 the SiC 2 and Ti, Mo, W / (1-x) Ti 3 SiC 2 -xSiC layered composites, Ti, Mo, W / Ti 3 SiC 2 layered material interface and high-temperature The thermal stability study. Titanium powder, silicon powder, graphite powder as raw material, non-pressure sintering Ti 3 SiC 2 materials. Due to the low melting point of silicon, is highly volatile in the sintering process and, therefore, the silicon content of the raw materials the composition of the sintered product to a great influence. The experimental results show that the ratio of using original elements Ti 3 Si 1.1 C 2 , less impurity content in the sintered product. The the pressureless sintering prepared Ti 3 SiC 2 block after grinding sifting can be particles of about 10 μm Ti 3 SiC 2 powder, its copper plating by chemical methods, and prepared Cu powder mixed with warm compaction, sintering process the different Ti 3 SiC 2 content the Cu matrix composites, and rolling processing. The results showed that Ti 3 SiC 2 content of 5 wt% of Cu-based composite material has good mechanical properties, and when a deformation rate of 30%, the sample has a good mechanical properties and resistance to friction and wear ability, the density of up to 8.28 g / cm 3 , the tensile strength of 288MPa, a resistivity of 7.0 × 10 -8 Ωm hardness of HB106 , the friction coefficient was 0.17. To explore metal - ceramic connection This selection of the Ti 3 SiC 2 ceramics and is suitable as a high temperature, wear-resistant materials and nuclear installations Preparation of SiC ceramics (1-x ) Ti 3 the SiC 2 -xSiC composite materials as metal-SiC composites in the middle of the transition layer. Titanium powder, silicon carbide powder, graphite powder as raw material, can be prepared by 1500 ℃ pressureless sintering composites (1-x) Ti 3 SiC 2 -xSiC its low density, spark plasma sintering technique can be prepared in line with the component design requirements (1-x) Ti 3 SiC 2 -xSiC composites, only a very a small amount of an impurity phase exists, and the density of more than 95%, but the sintering temperature is higher, and the SiC content is different, the optimum sintering temperature of the composite material also changes. Using titanium powder, silicon powder, graphite powder as raw material, and aluminum powder as sintering aids, 15 min can be prepared by to 1300 ℃ SPS sintering the pure 0.9Ti 3 the SiC 2 -0.1SiC containing a small amount of residual C the 0.8Ti of 3 the SiC 2 -0.2SiC composite. With increasing SiC content in the design component, the density of the composite material bending strength decreased but the Vickers hardness, and resistance rates increased. Titanium powder, tungsten powder, molybdenum powder, silicon powder, graphite powder as raw material, the addition of Al powder as a sintering aid, spark plasma sintering technology can be successfully prepared Ti, Mo, W / Ti 3 SiC 2 layered composite material and its flexural strength and interface thermal stability. Experimental results show that Ti, Mo / Ti 3 SiC 2 layered composite density and flexural strength were higher than the W / Ti 3 SiC 2 layered composite Ti / Ti SiC 2 layered composite interface intermediate buffer layer of Ti / Ti TiC / TiC Ti < sub> 5 Si 3 C x / Ti 5 Si 3 C x < / sub> / Ti 3 SiC 2 Mo / Ti ,, SiC , 2 layered composite interface intermediate transition layer Mo / Mo 2 the C / MoSi 2 / Ti 5 Si 3 C x 2, sub> / Ti 3 W / Ti 3 SiC 2 layered composite interface intermediate transition The layer is a compound of the W and C. Ti 3 SiC 2 , Ti , 3 SiC 2 -SiC and Ti, Mo, W / Ti 3 SiC 2 Preparation of layered materials basis, the use of spark plasma sintering technology to prepare Ti, Mo, W / (1-x) Ti 3 SiC 2 -xSiC multilayer layered composites. Transition layer interface are straight and clear interface are linked closely together, and there is no obvious holes, cracks appear.
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