Abstract
We investigate the mechanical characteristics of S45C/Cu/Si_3N_4 structures subjected to thermal loadings. First, thermal loading tests are conducted under various heat conditions. Next, four-point bending tests are conducted to evaluate the stress-strain curves and residual strength. The results reveal that thermal loadings cause fatigue damage to the Cu interlayers and its amount increase with increases in the cycle number and temperature range of thermal loading. The increases in the cycle number and temperature range promote reductions of fracture ductility, Young's modulus and residual strength for S45C/Cu/Si_3N_4 structures. It is found that the reductions of the mechanical characteristics of the S45C/Cu/Si_3N_4 structures are affected by the fatigue damage of the Cu interlayers.
