The effect of cold plastic deformation between solution treatment and artificial aging on the age-hardening response and mechanical properties of alloy was investigated by micro-hardness test,tensile test,optical microscopy (OM) and TEM observation.After solution treatment at 420 ℃ for 1 h,three kinds of pre-deformation strains,i.e.0,5％ and 10％,were applied to extruded ZM61 bars.Age-hardening curves show that pre-deformation can significantly accelerate the precipitation kinetics and increase peak-hardness value; however,as pre-deformation strain rises from 5％ to 10％,there is no gain in peak hardness value.The room temperature (RT) tensile properties demonstrate that increasing the pre-deformation degree can enhance the yield strength (YS) and ultimate tensile strength (UTS) but moderately reduce elongation (EL); furthermore,the enhancement of YS is larger than that of UTS.No twin can be observed in 5％ pre-deformed microstructure; however,a large number of twins are activated after 10％ pre-deformation.The peak-aged TEM microstructure shows that pre-deformation can increase the number density of rod-shaped β1'precipitates which play a key role in strengthening ZM61 alloy.%采用显微硬度测试、拉伸试验、金相观察和TEM观察,研究冷塑性变形对Mg-6％Zn-1％Mn (ZM61)合金时效硬化和力学性能的影响.在420℃固溶处理1h后,对ZM61挤压棒材试样进行室温拉伸变形,塑性应变有3种:0、5％和10％,预变形后再进行人工时效.时效硬化曲线表明:预变形可以显著加快硬化速率且提高峰值硬度；然而,当应变量由5％增加到10％后,峰值硬度并未增加.室温拉伸性能表明:预变形量增加,屈服强度和抗拉强度增加,伸长率略有降低,且屈服强度的增加幅度大于抗拉强度的.金相组织观察表明:当预变形应变量为5％时,金相组织中未观察到孪晶；预变形10％的组织中出现了大量的孪晶.TEM观察表明:预变形可以增加峰时效态组织中β1’杆状相的数量.
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