Control of Foaming of Al Alloy Melt

抄録

The optimal quantity of TiH 2 (foaming agent) and the most suitable temperature for producing foamed Al alloy in a non-isothermal process are determined. Experimental results show that the initial foaming temperature must be higher than the solidifying point of Al alloy, and as TiH 2 decomposition starts, the melt temperature drops down to the solidification temperature interval, meanwhile bubbles become stable and drainage of foaming layer slows down. In the experiments, foaming temperature of 680°C and 2 wt% 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.