Process optimisation in the squeeze casting of zinc–aluminium alloys and composites

Squeeze casting is a process which has the potential to produce castings with exceptional mechanical properties. It also appears to be the most suitable route to produce sound cast metal matrix composites. An investigation was carried out into the squeeze casting of four zinc–aluminium alloys: commercial ZAS (simple eutectic alloy); commercial ZA12 (simple eutectic alloy); commercial ZA27 (peritectic alloy); binary Zn-37Al (solid solution alloy). Although the three commercial alloys can be cast by a variety of conventional gravity and pressure processes it was considered that squeeze casting would produce castings with more homogeneous microstructures and enhanced room temperature properties. The binary Zn-37Al was considered to be a suitable alloy for squeeze casting. [Continues.]