助烧剂与脱胶工艺对微波烧结Al_2O_3陶瓷性能的影响

Effect of Sintering Aids and Degumming Process on Properties of Microwave Sintered Al_2O_3 Ceramic

采用微波烧结方式制备Al_2O_3陶瓷,研究了助烧剂含量和素坯脱胶工艺对Al_2O_3陶瓷微观组织和力学性能的影响。研究结果表明:相较于传统无压烧结,微波烧结有利于降低Al_2O_3陶瓷的烧结温度,并提高致密度和力学性能。脱胶后烧结体晶粒结合更加紧密,界面结合强度有明显提高,断裂模式以穿晶断裂为主。当Mg O与Y2O3添加量为0.7wt%时,Al_2O_3陶瓷致密度稳定在99.1%以上,断裂韧度和维氏硬度分别达到4.9 MPa·m1/2和17.0 GPa。

Microwave sintering was applied in this study to prepare alumina ceramics. The sintering aids and green body degumming process before microwave sintering were optimized. The results showed that the microwave sintering was beneficial to reduce the densification temperature of Al2O3 ceramics and could improve the density and mechanical properties of the ceramics compared to the traditional pressureless sintering. The grain of the sintered sample bound more tightly and the interface bonding strength was improved obviously after the degumming process,and the transgranular fracture was the mainly fracture mode. When 0. 7 wt% Mg O and 0. 7 wt% Y2 O3 were added the density was stable at over99. 1%,the fracture toughness and the hardness of the sample were 4. 9 MPa·m1/2 and 17. 0 GPa.