SYNTHESIS AND CHARACTERIZATION OF Al FOAMS PRODUCED BY POWDER METALLURGY ROUTE USING DOLOMITE AND TITANIUM HYDRIDE AS A FOAMING AGENTS

摘要

Production of aluminum foams by the powder-metallurgy process depends on the preparation of pre-cursors. In general, pre-cursors consist of compacted mixture of metallic powder and foaming agent, which is foamed at a pre-determined temperature. Due to high temperature of foaming procedure, the foaming agent decomposes into a solid component that is built into the matrix material, and a gas component that causes foaming of the matrix material. Powder metallurgy is a method for making close-cell foams and it is the best selection, especially for the production of net-shape parts, providing excellent quality of end products. In our research work, powders, precursors and foams, made from different metallic powders (Al 99.7 % purity, AlSi12 alloy) with different foaming agents (TiH2, CaCO3, CaMg(CaCO3)(2)), were examined with different analytical techniques.