Numerical analysis of residual stress in ceramics/metal brazed joints

The residual stress in ceramics/metal joints was calculated by thermal-elastic-plastic finite element method in this paper.The influence of temperature on the material properties and the interface reaction layer was taken into account.The radial stress and shearing stress had a little influence on the joints,but a peak axial tensile stress which influenced on load-bearing capacity of joints occurred at the ceramic surfaceson the edges.The maximum of residual stress of Si₃N₄/40Cr brazed joints is higher than that of Si₃N₄/45 steel joints,because yield strength of 40 Crsteel is higher than that of 45 steel.Though the reaction layers of inter-faces are thin,they are important factors which influence on residual stress.In addition,the peak residual stress can be reduced by appropriate filler metal,interlayer and brazing pressure.