DISSIMILAR MATERIALS JOINING OF STAINLESS STEEL AND POLYAMIDE 6 BY FRICTION LAP JOINING

摘要

As a thermoplastic plastic, polyamide (PA) has found significant applications in automobile, aerospace structure due to low weight and good mechanical properties. However, structure coupling of PA with metal using mechanical fastening and adhesive bonding raised weight penalties and lower environment compatibility. This has motivated novel approaches development for dissimilar joining of PA and metals. In the past decade, welding of hybrid plastics and metals has been attempted. Among them, laser direct joining method was developed to produce strong dissimilar joints between metals and plastics [1], named as LAMP. LAMP was characterized by plastics flowing driven by high pressure caused by a rapid expansion of bubbles generated by the melted plastics. The other successful one was friction spot joining (FSpJ), also known as re-fill friction stir spot welding. During FSpJ, a mixed regime of the hybrid materials with surface mechanical interlocking was responsible for the dissimilar joining of FSpJ and very high strength was exhibited [2].