Residual stresses which developed through the molding process of epoxide composite with metallic electrodes embedded were studied.
Viscoelastic properties of the epoxy were obtained by bending creep tests under constant temperature conditions and the validity of the time-temperature superposition principle was verified through the tests under slowly varying temperature conditions.
The residual strain measurements were conducted using circular epoxy plates in which Cu or Al electrodes were embedded. The comparison of the results with the linear viscoelastic solutions of the residual strains obtained by assuming linear cool-down from Tg to room temperature showed good agreement, and it was suggested that the simple elastic FEM solution was applicable for practical applications.
The long-term change in residual stress of the epoxy plate with metallic electrodes embedded placed in a cyclically fluctuating temperature atmosphere was estimated based on the theory of linear viscoelasticity and the related thermal fatigue strength was discussed.