基于响应面法的氧化物结合碳化硅材料制备工艺优化

Optimization of preparation technology for oxide-bonded silicon carbide materials based on response surface methodology

以碳化硅和高岭土为原料,利用原位反应合成法制备了氧化物结合碳化硅材料,并基于响应面法,采用材料显气孔率、常温抗折强度和热震稳定性为评价指标,研究了热处理温度、成型压力和高岭土添加量对材料性能的影响。模型分析及验证性实验结果表明,制备氧化物结合碳化硅材料的最佳热处理温度、成型压力以及高岭土添加量分别为1400℃、80 MPa、10%,在该工艺条件下所制材料的显气孔率、常温抗折强度以及残余强度保持率分别为15.9%、22.7 MPa、45.8%。

Oxide-bonded silicon carbide materials were in-situ synthesized by using SiC and kaolin as raw materials, and the effects of heat treatment temperature, molding pressure and kaolin content on material properties were investigated based on the response surface methodology with apparent porosity, cold modulus of rupture and thermal shock stability as evaluation indexes.The results of model analysis and confirmatory experiments show that the optimum heat treatment temperature, molding pressure and kaolin content for the preparation of oxide-bonded silicon carbide material are 1400 ℃,80 MPa and 10%,respectively.Under the described conditions, the apparent porosity, cold modulus of rupture and residual strength retention rate of the as-prepared material are 15.9%,22.7 MPa and 45.8%,respectively.