Effect of porosity of aluminum foam on welding between aluminum foam and polycarbonate plate during friction welding

The friction welding of aluminum foam with porosities p = 60, 70, and 80% and a dense polycarbonate plate was performed. The effect of the porosity of aluminum foam on the welding was investigated. It was found that aluminum foam fabricated by sintering and dissolution process can be welded to a polycarbonate plate by friction welding with pore structures retained. In addition, the polycarbonate infiltrated into the surface pores of aluminum foam, indicating that the welding was achieved through the anchor effect. Welded samples were subjected to tensile tests to determine where fractures occurred. For aluminum foam with p = 80%, since all fractures occurred in the aluminum foam part, the obtained welding strength was higher than that for the base aluminum foam with p = 80%. For aluminum foam with p = 60%, all fractures occurred at the weld interface, indicating that the welding strength of this foam was lower than that of the base aluminum foam with p = 60%. For aluminum foam with p = 70%, the fracture occurred at the aluminum foam part or at both the aluminum foam part and the weld interface, indicating that the tensile strength of the base aluminum foam and the welding strength derived from the anchor effect were almost the same.