<i>In-situ</i> X-ray transmission observation of resin impregnation behavior during friction welding of porous aluminum and thermoplastic resin

Porous aluminum is aluminum with numerous pores inside, and is lightweight and has excellent shock-absorbing properties. Because of these characteristics, porous aluminum is expected to improve fuel efficiency and collision safety performance when used in structural components such as automobiles. However, it has disadvantages of low tensile and bending strength. In this study, we attempted to join polycarbonate plate (PCTA) and porous aluminum with dissimilar materials by friction welding. In order to clarify the softening behavior of PCTA and the impregnation behavior of PCTA into the pores of porous aluminum during friction welding, in-situ observation near the joining interface during friction welding was conducted by X-ray transmission. The results suggest that the area of softened PCTA can be controlled by indentation time, and that the upset pressurization is highly effective in promoting the impregnation of PCTA. When the area of softened PCTA became too large, there was less resistance during upset pressure, and PCTA was ejected as burrs from the joining interface.