挤压温度对Mg-Zn-Mn变形镁合金组织和性能的影响

对新型变形镁合金Mg-6%Zn-1%Mn铸锭在320、360、420℃等不同温度下进行挤压实验,成型后实施不同热处理,并分析不同状态下合金的微观组织和力学性能.结果表明:在320~420℃条件下,该合金能实现平稳地挤压成型并完成动态再结晶.挤压温度越低,再结晶晶粒越细小,挤压棒材性能越好.高温(420℃)挤压成型,动态再结晶越易进行,且再结晶晶粒越均匀,更有利于后期通过热处理改善合金性能.

Effects of extrusion temperature on the microstructure and mechanical properties of a new Mg-Zn-Mn alloy

The extrusion processes of the wrought Mg- 6wt. % Zn- 1wt. % Mn casts at 320℃,360℃,420℃ and the different follow- up heat treatments were studied in this research. The tensile mechanical properties and microstructure of the alloys under different treatment conditions were tested. The results showed that the new ZM61 alloy could be smoothly extruded between 320℃ and 420℃,while complete dynamic recrystallization took place during the extrusion. This method could get better extruded sticks and tiny recrystallization grains at the lower extrusion temperature. When the extrusion temperature was at a high temperature( 420℃),its dynamic recrystallization became easier,and the size of grains became more uniform,which was good for improving the properties of alloys through heat treatments at a later stage.