Castability of Al—Li alloys

The casting characteristics of various Al—Li alloys were investigated. Li losses in Al—3%Si—1%Mg—0.15%Zr containing 1,2 and 3% Li are about 0.1, 0.2 and 0.4%, respectively when the alloys were melted and held for 3 ks at 973 K in air. The hydrogen content of molten Al-Li alloys is lowered from 1.00 ml/100 g to 0.75 ml/100 g when the Ar degassing time is extended from 300 s to 1.8 ks at 973—983 K. The phenol resin-bonded sand mold coated with MgO, heated and then cooled in vacuum is suitable for casting of Al—Li alloys. The fluidity of Al—2%Cu—1%Mg—0.15%Zr and Al—3% Si—1%Mg—0.15%Zr alloys is not almost changed by the addition of Li up to 3%. The fluid length of these Al—Li alloys is inferior around 85% to that of AC4C (Al—7%Si—0.3%Mg).