Bending Strength and Singular Stress Field Analysis of Joints

J. Ocean Eng. Technol. 1998;12(4):25-32.

Sun-Chul Huh;Young-Chul Park;Doo-Pyo Yun;

접합재의 굽힘강도와 응력특이장해석

허선철;박영철;윤두표;

동아대학교 생산기술연구소 특별연구원;동아대학교 계계공학과;동아대학교 대학원 기계공학과

Keywords: Rexidual stress, Repeat thermal cycle, Thermal expansion coefficient, Stress singularity index, Stress singularity Intensity,

핵심용어: 잔류응력, 반복열사이클, 열팽창계수, 응력특이성지수, 응력특이성강도,

Abstract

"Since the ceramic and metal are joined at high temperature, the residual stress will develop when it is cooled from bonding temperature due to remarkable difference of thermal expansion coefficient between ceramic and metal. Moreover, the edge of jointed interface makes singular stress field and this singular sσess field influences on the strength of joints. In this study. The effects of residual stress, mechanical load and repeat thermal cycle were estimated in the ceramic/metal joints. The change of singular stress field due to these effectswas analyzed. The results are as follow : 1) Strength of jcints was evaluated by the sσess singularity index λ and the intensity K of singular stress field. 2) The stress singularity index λ and the intensity K of singular stress field also increase as temperature of thermal cycle and its number of cycle increase. 3) In the case of mechanical load, the effect of residual stress reduces since the difference(Δλ) of stress singular index between existence and inexistence of residual stress decreases in proportion to the increasing of tensile load. "