制备莫来石泡沫陶瓷的工艺因素

Process Factors in Prepared of Mullite Porous Ceramic

采用红柱石和α-Al2O3为原料,以聚苯乙烯粒子(EPS)为造孔剂,通过烧结法制备莫来石泡沫陶瓷。借助XRD和SEM分析获得莫来石相的组成和形貌,通过正交试验,探讨了粘结剂加入量、造孔剂粒度及球磨时间等工艺参数对泡沫陶瓷结构和性能的影响,在此基础上进一步讨论造孔剂加入量对密度和强度的影响。结果表明:粘结剂加入量对密度和强度的影响较大,造孔剂粒度次之,球磨时间影响最小。1450℃烧结,红柱石和氧化铝按质量比80:20,EPS粒径小于0.60mm、加入9wt%造孔,可以制备性能优良的莫来石泡沫陶瓷,其表观密度0.52g/cm3,孔隙率为83%,抗折强度1.54MPa。

Mullite porous ceramic has been prepared through sintering process, using andalusite and alumina as raw materials, with EPS as pore-forming agent. The phase and microstructure of mullitization were analyzed by XRD and SEM. Binder addition amount, pore size of EPS and milling time have effects on properties to be investigated by means of orthogonal experiment. A further research was performed on the relationship between density and strength with the increase of EPS addition amount. It is found that the most effective factor on the bulk density and flexural strength is the binder addition amount, then the grain size of EPS and the milling time the least. When sintering temperature is 1450℃, EPS grain size is less than 0. 60ram and addition amount is 9wt%, the mass ratio of andalusite to alumina is 80 ： 20, the mullite porous ceramic with high performance can be given. Its apparent density is 0. 52g/cm3 , porosity is 83% and flexural strength is 1.54MPa.