Prediction of warp deformation for four-layer laminated structure containing resin by thermal load

Abstract

The warp deformation behavior for various viscoelastic four-layer laminated structure consisting of epoxy resin, printed board and steel which modeled electronic devices caused by a series of thermal load from heating to cooling was examined by experiment and viscoelastic stress analysis based on linear viscoelastic theory. As a result, it was clarified that the warp deformation behavior of laminated structure containing resin was influenced by thickness and viscoelastic properties of epoxy resin and printed board such as modulus of longitudinal elasticity and thermal expansion coefficient depending on temperature and time, and that the warp deformation behavior of viscoelastic four-layer laminated structure was determined by the balance between flexural rigidity of laminated structure and bending moment caused with the thermal expansion or shrinkage of constituent materials. The warp deformation behavior of laminated structure containing resin could be predicted in general by analysis in consideration of the characteristic of viscoelasticity.