AZ91镁合金热挤压变形的力学模型研究

在应变速率为0.01～50s-1时、温度为300～450℃条件下,在热压机上对AZ91镁合金的高温热压缩变形特性进行了研究,并通过金相显微镜观察合金热变形过程中的组织变化情况.研究发现,应力、应变曲线随温度的升高而降低,随应变速率的升高而升高.为了消除热电偶测温的滞后性对试样温升的影响,对实测流变应力值进行了修正.在相同应变速率、相同应变下,修正的应力要高于未修正的应力.

Research on Mechanical Model of AZ91 Magnesium Alloy During Hot Compression Deformation

The hot compression tests of AZ91 magnesium alloy were performed on warmpress at strain rates 0.01～50s-1 and deformation temperatures 300～450℃,and the microstructures of AZ91 magnesium during compression were observed by microscope.The results show that with the increase of temperatures and the decrease of strain rates.the stress-strain curves decrease.In order to eliminate the influence of temperature rise induced by hysteresis of thermocouple thermometer,the actual measured flow strees are corrected.The corrected flow stress is generally higher than the uncorrected at the same swain rates and strain.