增韧莫来石陶瓷工作热应力探讨

DISCUSSION ON THERMAL STRESS OF ZIRCONIA-TOUGHENED MULLITE CERAMICS

莫来石陶瓷是一种有潜力应用在高温条件下的结构材料，因为它具有较低的热膨胀系数和较高的抗蠕变性，且具有高温下陶瓷力学性能增高的特点．然而为改善陶瓷性能往往在莫来石基体中引入氧化锆增韧剂．由于基体与增韧剂之间的热失配，导致该陶瓷抗热震性降低．本文从分析陶瓷的高温热应力入手，通过添加氧化磷提高陶瓷抗热震性．

The mullite ceramics is thought to be a potential candidate for hightemperature application because of its low thermal expansion coefficient and high creep resistance,as well as its characteristic of an increase of ceramic mechanical properties at high temperature. However,the Zirconia toughening anents are often added to mullite matrixes for the purpose of improving ceramic properties,which make thermal shock resistance of ZTM ceramics decrease because of existence of the thermal mismatch between the matrixes and the toughening agents. In this paper,the thermal stress of the ceramics at high temperature is analyzed,so as to enhance the thermal shock resistance of ZTM ceramics by adding P2O5.