Control of foaming of Al alloy melt

The optimal quantity of TiH2 (foaming agent) and the most suitable temperat ure for producing foamed Al alloy in a non-isothermal process are determine d. Experimental results show that the initial foaming temperature must be h igher than the solidifying point of Al alloy, and as TiH2 decomposition sta rts, the melt temperature drops down to the solidification temperature inte rval, meanwhile bubbles become stable and drainage of foaming layer slows d own. In the experiments, foaming temperature of 680 degrees C and 2wt% TiH2 (<300 mesh) are the optimal combination for making foamed Al alloy of good quality. It is found that the wide solidification temperature region is an important factor for better controlling the foaming process.