| The laminated ternary carbide Ti3SiC2, which is a new kind of structural ceramics material, becomes the focus of material researchers attributing to its perfect combination of both merits of metals and ceramics. Like metals, it is a good thermal and electrical conductor with relatively lower Vickers microhardness, high modulus and ductility. Meanwhile it also exhibits some properties of ceramics such as excellent mechanical properties, high temperature stability, good resistance to thermal shock and high temperature oxidation. Most interestingly, unlike conventional carbides, it can be easily machined by regular tools without lubricant, which is of great technological application potential. Moreover, Ti3SiC2 is an exceptional solid lubricant with an ultra-friction coefficient lower than MoS2 and graphite. It is these excellent properties mention above that makes it be possible candidate in many application fields. To date, many methods, such as chemical-vapor deposit (CVD), self-propagating high-temperature synthesis (SHS), solid liquid reaction, mechanical alloying, hot pressing (HP), hot isostatic pressing (HIP) and spark plasma sintering (SPS), have been proposed to fabricate Ti3SiC2 material. However, it is very difficult to obtain a single-phase product. What we gain is often accompanied by unacceptably large amounts of impurities, such as TiC and titanium silicides(TixSiy).In this work hot pressing sintering was used and an idea of additive of aluminum was proposed to fabricate single-phase Ti3SiC2. Results showed that high purity dense Ti3SiC2 sample could be synthesized by hot pressing the powder mixtures with composition of 2TiC /ITi/ (0.9-1.0) Si/ (0.3-0.2) Al in molar ratio in the temperature range of 1300~1400℃ and under a pressure of 30MPa in argon flow.Additive of aluminum could accelerate the growth of grains and densification of Ti3SiC2. The content of Ti3SiC2 in the samples sintered at 1400 was 98.2 percent and the relative density was 98.8 percent of theoretic density. The calculated crystal lattice of the as-sintered samples were a=0.3063nm and c=1.7645nm, respectively, which were in good agreement with those in literatures. It meant that Al atom soluted in Ti3SiC2 sample and didn't change its crystal structure remarkably.The physical properties and high temperature oxidation resistance of the Ti3SiC2 samples were studied. Results revealed that Ti3SiC2 possessed excellent mechanical, electrical and thermal properties. The results of oxidation resistance test showed that additive of aluminum could increase the purity of samples and reduce the presence of secondary phase. A dense protective scale, mainly a-Al2O3, formed on the surface of the samples, which could prevent samples from further oxidation. It was helpful to improve its high temperature oxidation resistance and shed new light on the application in high temperature circumstance.
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