Fabrication of open-cell porous aluminum by friction powder sintering process

A new friction powder compaction process by the sintering and dissolution process route for fabricating open-cell porous aluminum (Al), which requires no external heat sources except friction heat, was developed. The sintering of the mixture of Al and NaCl powders was conducted only by a rotating tool plunged into the mixture. Namely, the sintering of the mixture was achieved because of the friction heat and pressing load generated by the rotating tool plunged into the mixture. In this study, porous Al with porosities of 60%, 70% and 80% were successfully fabricated. Their pore structures were observed by SEM and X-ray computed tomography (CT), and their mechanical properties were investigated by compression tests. It was found that almost the entire specimen had pore structures similar to the NaCl morphology regardless of the porosity. Plateau stress decreased with increasing porosity indicating strong relationships between them. Porous Al exhibited ductile fracture regardless of its porosity, which is considered to be attributed to the good bonding between Al particles. (Received April 20, 2014 Accepted July 31, 2014)