Development of Joining Method by Cylindrical Pin Using Thermal Expansion of CFRTP

Abstract

This study is focused on the expansion properties of CFRTP plate in thickness direction when it is heated at a temperature near the melting point of matrix resin. The purpose of this study is to investigate the usefulness of homo- and hetero-junctions with pins utilizing these expansion properties. In the study, two steel plates with a straight or tapered hole were heated to an appropriate temperature, and a cylindrical pin made of a laminated CFRTP was inserted into the hole on the plates stacked each other so as to align the positions of each hole. By heating the pin through the heated steel plates so as to generate volumetric expansion force against the wall of each hole, we have developed a new joining method of metal pieces with CFRTP pin. Experiments were performed on the new joining method. Moreover shear strength and tensile strength were evaluated. In this evaluation, it was confirmed that there is a relationship between volumetric expansion of CFRTP by heating and joint strength. It was further found that high joint strength was obtained by application of tapered hole on the steel plates.