Reliability evaluation of joints of ceramics and metal (1st report, consideration on thermoelastic-plastic stress around the interface of joined dissimilar materials)

The development of reliable bonding techniques for ceramics and metals is considered very important for more useful applications of ceramics. Generally, however, it is a serious problem that ceramics have a high thermal stress concentration at the bonded interface, caused by different thermal properties of the two materials. The authors have been investigating various methods for effectively decreasing the stress concentration. In this paper, they present a fundamental consideration on the thermal stress distribution characteristics at the interface of dissimilar material joints by using thermoelastic-plastic finite element analysis. Through this analysis, it is found that a high thermal stress is induced only in a very narrow region, and that the value of the high stress may be approximately estimated by a simplified theoretical analysis.