方石英的含量对氧化硅陶瓷型芯性能的影响

以石英玻璃粉为基体,方石英为矿化剂,陶瓷铸造蜡为增塑剂,利用热压注法制备了氧化硅陶瓷型芯,研究了方石英添加量对氧化硅陶瓷型芯性能的影响。研究结果表明:随着方石英添加量的增加,陶瓷型芯样品中石英玻璃析晶含量先增大后减小,样品的收缩率及高温挠度逐渐减小,高温强度先增加后减小,显气孔率随方石英添加量的增加逐渐增大。经验证,在烧结温度为1200℃下,方石英的最佳添加量为5%时,氧化硅陶瓷型芯的综合性能最好。

Effects of Cristobalite Content on Properties of Silica Ceramic Cores

The ceramic core was successfully prepared by the hot injection method, where quartz glass powders were used as starting materials, cristobalite as additive, and the ceramic casting wax as the plasticizer. The effect of cristobalite content on the properties of silica ceramic core was investigated. The results showed that the degree of crystallization of fused silica increased first and then decreased with the increase of the amount of additive cristobalite;the shrinkage rate, high temperature deflection of samples decreased gradually with the increase of the amount of additive cristobalite;the high temperature strength increased first and then decreased with the increase of the amount of additive cristobalite, and the apparent porosity increased gradually with the increase of the amount of additive cristo-balite. It was proven that the ceramic core with 5wt% cristobalite content has the best comprehensive properties at 1 200 ℃.