中间层厚度对陶瓷扩散焊接头应力分布影响的数值分析

采用有限元计算方法，对平面应变、平面应力两种应力状态下含中间层的陶瓷接头界面上应力分布规律进行数值分析。得到了接头界面上正应力和剪应力沿板定的分布曲线。结果表明，中间层材料厚度小时，两种应力状态下的正应力和剪应力在接头界面上滑板定的分布基本均匀。中间层材料厚度增大，平面应变状态下试件中部的正应力增大并出现峰值；平面应力状态下在试件自由瑞边缘正应力增大并出现峰值。两种应力状态下界面上的剪应力由板中央到板边缘逐渐增大，界面上边缘处最大剪应力的值也随中间层厚度的增加而增大。因此，在保证接头接合良好的前提下，应采用小厚度的中间层。

NUMERICAL ANALYSIS OF THE EFFECTS OF INTERLAYER WIDTH ON THE STRESS DISTRIBUTION IN DIFFUSION BONDED CERAMICS JOINTS

Stresses distributions of diffusion bonded joints with interlayer are studied using the finite element method. the curves of normal stress and shear stress distribution are obtained for joints with different in-terlayer width under plane stress condition and plane strain condition. The results show that when thewidth of the interlayer is small the normal stress and shear stress distribute almost uniformly, with the in-crease of the interlayer width, where the normal stress increases and has a peak value in the middle part ofthe specimen under plane strain condition, and has a peak value on the edge of the free end of a specimenunder plane stress condition. the shear stresses of both stress conditions increase with the increase of thedistance from the central line of a specimen. The maximum of the shear stress near the edge of a specimenincreases with the increase of interlayer width. lt is concluded that a small width of interlayer should beadopted under the condition that the joints are well bonded.