| Sintering is a kind of phenomena which can produce ankylosis between grains under heating up ,and it is the last and the most important tache when you want to get the expecting material.This paper is studying the sintering properties of SiC-Sialon which is prepared by gelcasting ,and one-step-compounding method of formingβ-Sialon was applied in this job,we have found the influencing rule of grain composing ,value of different Z ofβ-Sialon,sintering temperature on the properties of SiC-Sialon.The above work is an important guiding scheme in our practicing produce.The sintering properties of SiC-Sialon which is made of Si,Al,SiO2,and SiC powder have been studied systematically. the results showed that the hexastyle shape crystallite ofβ-Sialon is the best when the value of Z is 2,and at this time the properties of the ware is optimum.If the value of Z is too little or too big,the properties of the ware will be influenced.When the value of Z is 2,the ware can be sintered well at 1550℃,or if it is too high ,the volume density,blending strength,compressive strength,and opening porosity will be influenced. The ware's properties is the best when there are three kind size's grain in the body,this is because if we are according to academic grain grading in gelcasting ,the big grain is too many to suspend,at last,the proportion of the tree kinds grains which has been justed is 5:1:4; TiO2 or Guangxiniantu is the best sintering additive,which has been attested through optimizing experiment.We have studied the possibility which can formβ-Sialon from the view of the thermodynamic and dynamic,and the nitridation reaction in which the perfect model is used whenβ-Sialon is forming .besides this ,we have foundβ-Sialon's nitridation reaction is the most complete at 1550℃when the value of Z is 2 from the angle of nitridation reation rate constant and activation energy.
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