Promising High-Speed Welding Techniques for Joining Polymers to Metals and Underlying Joining Mechanisms

Abstract

Strong dissimilar material welds (DMW) of PA66 and 6061 Al was produced by friction lap welding (FLW) at welding speeds as high as 5 m/min. The temperature difference at various locations of the welds did not affect the local joining strength. In an attempt of explaining the joint strengths, special samples were made by evaporation of aluminum oxide onto a polyamide 66 (PA66) substrate to form metal/polymer interface. X-ray photoelectron spectroscopy (XPS) analysis showed that the key chemical bond developed across the PA66/alumina interface is of Al–O–C type which would have very likely contributed to good joint strengths in such metal/polymer joints. Elevated temperatures are not essential for formation such chemical bonds as long as a fully intimate atomic contact between the PA66 and Al plates can be achieved.