Solidification Structure and Strength of Zn-4 Al-X Cu Alloys

For developing high-strength Zn alloys, Zn-4 Al-X Cu-0.02 Mg (X=0∼10) alloys are examined. More than 3 % Cu-content alloy produces ε phase, which improves the strength of the alloys. The tensile strength of commercial alloy of ZAS (Zn-4.1 Al-3 Cu-0.04 Mg) for molds is 215 MPa, Z0408 (Zn-4 Al-8 Cu-0.02 Mg) shows 295 MPa. On the other hand, the casting of high Cu-content alloys for molds required high temperature, those of Z0408 is 823 K, while those of ZAS is 703 K.