Abstract
The effect of Mg vapor on Al sintering process has been investigated to manufacture open-cell high porosity porous Al material by Space Holder Method. It was found that Al-Mg oxide particles of 50-100 nm in size and exposed Al matrix were formed on the surface of Al sintered in Mg vapor. When the sintering temperature was higher than 915 K, droplets were formed below the melting point of Al, 933 K. It was supposed that Mg in sintering atmosphere could diffuse into Al powder surface and transform Al oxide film into Al-Mg oxide particles and exposed Al matrix by reduction, furthermore Mg diffusing into exposed Al matrix could lower the solidus and liquidus temperature of Al powder surface area and form liquid regions. These phenomena are effective for Al sintering process without forming excessive amounts of liquid. A temperature range of 905-910 K was suitable for sintering porous Al material in Mg vapor conditions of this work. Open-cell porous Al sheet with 88 % porosity and no inclusions in the neck boundary was obtained.
