Joining Mechanism of Dissimilar Materials such as Metal and Plastic Sheets by Friction Lap Joining

Abstract

It is difficult to join dissimilar materials such as metallic material and polymer. We have investigated to join Aluminum alloy and high density polyethylene (PE) and ethylene acrylic acid copolymer (EAA) using Friction Lap Joining (FLJ) and then concluded EAA could be strongly joined with Aluminum alloy. PE could not be joined without anodizing. We have considered that EAA has a polar functional group, COOH. On the contrary, PE cannot be joined to an as-received aluminum alloy, because PE has no polar functional group. So, we have tried to confirm this mechanism with XPS and FTIR to investigate the interface between anodized surface and that of polymer. We find that the possibility of chemical bonding arises between O-H in COOH and O in Al2O3or O in C=O and O in Al2O3 at elevated temperature.