Production of Al based metallic foam reinforced with particulate by powder metallurgy technique

Aim of this study was to investigate of production parameters of Metal Matrix Composite (MMC) foams produced by Powder Metallurgy (P/M) technique. In the study pure aluminium and prealloyed Alumix 231 ? based metal powders were used as a matrix material. Effects of foaming agent (TiH2) ratio (0,5%, 1%, 1,5% and 2%) and foaming temperatures (650°C, 670 °C, 690 °C and 710 °C) on the pore morphology , linear expansion coefficient and density of metallic foam were investigated. In production of MMC foam, Al/Alumix 231, TiH2 and Al2O3 powders were mixed in three dimensional turbola for 30 minutes. Mixed powders were compacted at 600 MPa, sintered at 550 °C for 2 hours and then hot deformed by 50%. Deformed MMC samples were foamed for 10 minutes. The samples produced with each matrix material linearly expanded in the deformation direction. It was found that, linear expansion ratio increased with increasing TiH2 ratio and foaming temperature. And also, pore cell thickness and metallic foam density increased with increasing Al2O3 ratio in the composite. To produce MMC foam, optimum experimental parameters were determined in TiH2 ratio of 1%, foaming temperatures of 670 °C - 710 °C and foaming time of 10 minutes.