This article mainly discussed the structure of Mg-7Gd-5Y-1.2Nd-Zr magnesium alloy as-cast. The behavior of alloy during the hot deformation process was investigated on Gleeble-1500D hot simulator with the strain rates 0.002

0.01

0.1

1 s-1 and the temperature range was 573 K to 723 K. The maximum deformation degree was 60%. It could be applied to practical hot working for magnesium alloy.The experimental results show that the relationship between stress and strain is obviously affected by the strain rate and deformation temperature. The peak flow stress becomes higher with increasing the strain rate at the same temperature

and becomes lower with increasing the deformation temperature at the same strain rate. The melting of eutectic structure during the hot deformation process was very important to decrease the flow stress.When the stain rate was 0.1/s

discontinuous recrystallization became obvious and it was a great disadvantage to the hot deformation process. The average deformation activation energy Q and the strain coefficient n were 243.5 kJ/mol and 4.2

also it was controlled by temperature directly and by strain rates indirectly.