Evaluation of Strength Characteristics of Ceramics/Metal Joints

Abstract

Tension tests were carried out on Si₃N₄/SUS 304 joints at room and high temperatures. Analyses were also conducted on the same specimens using the finite-element method to evaluate residual stresses and stress concentrations. The results can be summarized as follows: (1) The maximum tensile residual stress is axial stress σ_z which occurs at the same point, very close to the end of the joining interface, for every Cu thickness and temperature. (2) The maximum tensile stresses occurring in the ceramics/metal joints stressed under tension at room temperature are constant, independent of the interlayer thicknesses. The joint strength is dominated by residual stress and stress concentration. (3) The maximum tensile stresses in the ceramics/metal joints stressed under tension at high temperature decrease with the increase in temperature. Therefore, the joint strength is dominated by residual stress, stress concentration and the decrease in joint strength due to the increase in temperature.