Influences of rare-earth elements such as Y and Gd on the high temperature mechanical properties and microstructure of T4 treated AM60 magnesium alloy were investigated by tensile testing and OM（optical microscopy）and SEM（scanning electron microscopy）.The results show that rare-earth elements Y and Gd can restrian the AM60 alloy from softening through solid solution strengthening

and decrease the Mg17Al12 content as well as improving the softness and coarseness of the Mg17Al12 phase at130 ℃.The high melting new phases of Y

Gd with Al

Mg can enhance behavior alloy at 130 ℃.The tensile strength of the alloy with Y and Gd addition can reach 227 MPa and 236 MPa in as-cast and T4 treated conditions

increased by 12.4% and by 13.5%

respectively

compared with those of AM60 alloy with absence of RE addition.