The Study Of The Influencing Factors Of The Synthesis Of Ti₃AlC₂by SHS

Ti₃AlC₂is a novel structural and functional material which is concerned due to itsexcellent performance of metal and ceramic by materials scientists at home and abroad.It islike a metal with a lower Vickers hardness,good thermal and electrical conductivity at roomtemperature, good thermal shock resistance at high temperatures, and it has self-lubricatingproperties superior to graphite and MoS₂,It can be processed with a high-speed tool withoutlubricated;Ti₃AlC₂has a high melting point, high strength and good oxidation resistance likeceramic.The excellent performance indicates that Ti₃AlC₂materials will have a very broadapplication prospects.So far, hot pressing （HP）, hot isostatic pressing （HIP） and spark plasmasintering （SPS）, as well as self-propagating high-temperature synthesis （SHS） were used toprocess Ti₃AlC₂, expectations of high purity Ti₃AlC₂material, but the product obtained withmany impurities generation, purity is not very high.So this paper studies the influence of thedoping crew in the synthesis of Ti₃AlC₂materials by self-propagating high temperaturesynthesis.In this paper, Ti, Al, C and TiC powder as raw material are used to synthesis Ti₃AlC₂byself-propagating high temperature synthesis method.Studing the effect on the purity of thefinal product when Sn and Si two elements are doped in a certain ratio of raw materials.Anddiscussing the role of Sn and Si as additives in the reaction process.Last, Sn and Si are dopedinto the2Ti/Al/C simultaneously to prepare high purity Ti₃AlC₂.And the phase composition,morphology and reaction mechanism of the product with different parameters were discussedby many methods such as XRD, SEM and DSC.The experiment results show that the purity of Ti₃AlC₂is very high of2Ti/Al/C/0.9TiC/0.3Sn and2Ti/Al/C/0.1Si by SHS under the pressure of50MPa in airatmosphere,the mass ratio of steel balls to elemental powder is10:1, with milling speeding ofl50rpm, mixing time for4hours when doping with Sn or Si in the raw materials of Ti-Al-Calone.The purity of the product of2Ti/Al/C/0.2Sn/0.1Si is highest when doping with Sn andSi in the raw materials simultaneously and the crystal growth is best. By using Sn and Si as anadditive can effectively inhibite formation of Ti₂AlC.