Zn-al Matrix Composites - Investigation of the Thermal-expansion, Creep Resistance and Fracture-toughness

Composites of Zn-A1 alloys (ZA8 and ZA27) reinforced by fibres of alumina, carbon or steel have been prepared by squeeze casting. Microstructural observations reveal the segregation of the zinc-rich phase around the fibres. The composites exhibit a greatly reduced creep rate in comparison with the matrix alloys. The thermal expansion coefficient is also significantly decreased. The impact toughness has been studied by Charpy tests