2021 Volume 57 Issue 2 Pages 51-57
Residual stress at the interface between a glass fiber-reinforced phenolic resin having a fiber orientation and copper foil was analyzed in situ during curing and thermal-testing via time-resolved X-ray diffraction measurements using a sin 2 Ψ method, in which the specimen was prepared via a transfer molding. The residual stress, which was estimated from the stress in copper, shifted toward tensile and compressive stress directions in heating and cooling, respectively, due to a difference in the magnitude of thermal expansion and contraction between the resin and copper. There was an anisotropy of coefficient of linear expansion（ CTE） of the resin due to the fiber orientation, which caused a residual stress anisotropy. The temperature at a stress-free state indicated that the residual stress was also affected by a resin temperature at which the resin-copper adhesive interface first formed during molding.
