Mechanical characterization of E-glass laminates under large bending

This study focuses on epoxy fiberglass (E-glass) laminates used as printed circuit boards, more particularly as flexible substrates in fracture assemblies for the test of attachments of electronic components such as solder and adhesive joints. Breaking these joints often requires large bending of E-glass substrates. Such circumstances have not been investigated before. In fact, most research focused on the linear elastic behaviour of E-glass. Therefore, static large bending tests were conducted on instrumented cantilever and square plates. Test data consisting of pull force and strain versus deflection curves revealed that the behaviour of E-glass laminates is overall non-linear-elastic. Next, the correlation between simulated and measured structural responses of test prototypes led to determining E-glass lamina properties applicable upon large bending.