The effects of different Zr contents on the grain size and as-cast mechanical properties of the MgZn5Nd3.5 alloy were studied.Microstructural observation indicates that grain size is increased with increase in the Zr content in case of Zr content less than 0.8%

while the grain size is somewhat changed with that in case of Zr content more than 0.8%.From the mechanical property measurements indicate that Zr addition can improve as-cast tensile strength and elongation of the alloy.SEM analysis shows that alloy rupture changes from quasi-cleavage fracture to ductility fracture.