Porous aluminum has multi-functional properties. This is a lightweight metal and has excellent shock absorption, thermal insulation and sound absorption properties. In this study, two types of precursors, A1050 and A6061, were arranged in a line and foamed them by heating with halogen lamps. After foaming, we joined A1050 and A6061 porous aluminum by roller forming when A1050 reached 670°C. The X-ray CT images of the samples suggest that the oxide film was fractured due to material flow caused by roller forming. In addition, the porous structures were observed on the fractured surfaces after four-point bending test of the samples. This means that the joint strength of roller joining is higher than the base material strength of porous aluminum. In roller joining, it is suggested that the size of foaming is important because it is necessary to promote high material flow in porous aluminum and to fracture the oxide film.
Nagatake et al. (Sun,) studied this question.