PNNL

Abstract

This work investigates how multiple plasma surface treatments can significantly enhance adhesively-bonded metal-CFRTP (carbon-fiber-reinforced thermoplastic polymer) dissimilar joints, a topic that has been rarely investigated compared to other parameters during the plasma treatment process. By conducting Double Cantilever Beam (DCB) tests on adhesively bonded AA6061-CFRPPA (carbon-fiber-reinforced polyphthalamide) dissimilar joints, it was shown that the average Mode I specific fracture energy after 20 plasma treatments, using processing parameters without noticeably changing surface roughness, can be improved and saturated up to almost 2000% compared to non-treated joints and 240% compared to a single plasma treatment commonly used in the literature, due to the enhanced chemical bonding at the CFRPPA-adhesive interface. This study is important for achieving strong bonding performance of CFRTP-related structural joints using multiple plasma treatments, a simple and effective method.