Al_2O_3/Y_2O_3复合助剂对碳化硅蜂窝陶瓷烧结性能的影响研究

Study on Effect of Al_2O_3/Y_2O_3 Sintering Compositive on the Sintering Properties of SiC Honeycomb Ceramics

以碳化硅为主要原料,以羟丙基甲基纤维素(HPMC)为粘结剂,以Al2O3和Y2O3作为复合烧结助剂,采用挤出成型工艺制备出碳化硅多孔蜂窝陶瓷。探究了复合助剂Al2O3/Y2O3的加入量对蜂窝陶瓷物相组成和微观形貌的影响;研究了烧结温度对碳化硅陶瓷物相、微观形貌以及孔隙率、线收缩率、体积密度、抗压强度的影响规律。结果表明:Al2O3/Y2O3复合助剂的加入量增大和烧结温度的提高,陶瓷液相量增多;在钇铝石榴石(YAG)的共晶点1760℃附近,更易于析出结晶形成YAG相。烧结温度升高,陶瓷收缩率增大;体积密度和抗压强随烧结温度变化规律接近;体积密度和抗压强度在1750℃达到最大值分别为1.8 g/cm3和14.09 MPa。

SiC honeycomb ceramics were extruded using hydroxypropyl methyl cellulose（ HPMC） as the adhesion agent and sintered with Al2O3/ Y2O3 as the sintering agent. The influences of the adding amount of Al2O3/ Y2O3 on the micro component and morphology were explored,and the effect of temperature on the micro component and morphology as well as the properties as the open porosity,linear shrinkage,bulk density and the compressive strength were investigated. The results show that the amount of liquid phase increases with the rising adding amount of Al2O3/ Y2O3 and lifting of sintering temperature. The YAG phase is inclined to be formed near its eutectic point（ 1760 ℃）. The linear shrinkage elevates as a matter of the temperature; its changing regular turned to be the same as the bulk density and the compressive strength,which reach the upmost value 1. 8 g / cm3 and 14. 09 MPa,respectively,at 1750 ℃.