A method of heat treatment Mg-Al-Zn-Y of magnesium alloy

A method of heat treatment Mg-Al-Zn-Y of magnesium alloy, magnesium alloy ingot to hot extrusion process, an extrusion temperature of 340 ℃ ± 5 ℃, extrusion ratio 5 ~ 7, air cooled to room temperature after extrusion ; deformation after extrusion material is heat-treated: 5 ~ 7h first heated at 402 ℃ ~ 408 ℃, cooled to room temperature; and then incubated at 18 ~ 19h 180 ℃ ~ 190 ℃, and finally air cooling; the Mg-Al- Zn-Y magnesium alloy, the total weight percentage of the elements: Al is 8.3 ~ 9.7%, Zn 0.37 to 1.0%, by weight of rare earth elements of Y is 1.85% ~ 1.95%, the balance being Mg. The present invention is in conjunction with heat pressing and heat treatment, after the heat treatment, β-Mg17Al12 strengthening state extruded Mg-Al-Zn-Y of magnesium alloy are dispersed in the crystalline phase and the grain boundary precipitates more uniform small, rendering the resulting rare earth phase Al2Y passivation corners, and mainly distributed in the grain, so that the mechanical properties significantly.