AZ61镁合金热压缩流变应力的实验  

Study on Flow Stress of AZ61 Magnesium Alloy in Hot Compression Deformation

作　　者：王智祥[1] 刘金明[1] 刘柏雄[1] 刘斌[2] 

机构地区：[1]江西理工大学材料与化学工程学院,江西赣州341000 [2]华侨大学机电及自动化学院,福建泉州362021

出　　处：《华侨大学学报（自然科学版）》2009年第3期248-252,共5页Journal of Huaqiao University(Natural Science)

基　　金：福建省科技计划重点项目(2006H0029)

摘　　要：采用Gleeble-1500型热模拟机,对AZ61镁合金进行高温压缩实验,分析该合金在不同变形温度与应变速率条件下的压缩流变应力.研究AZ61镁合金在热变形时,流变应力与变形温度、应变速率之间的关系,并建立相应的流变应力模型.结果表明,AZ61镁合金在高温压缩变形时,当变形温度一定时,流变应力随应变速率的增大而增大;而当应变速率一定时,流变应力随变形温度的升高而降低.AZ61镁合金的热变形过程均表现出较明显的动态再结晶特征,其流变应力的变化规律主要受加工硬化和再结晶软化两者机制的共同作用.在热变形下,AZ61镁合金峰值流变应力可以用双曲正弦模型来进行较好的描述.Hot compression experiments of AZ61 magnesium alloy was performed on Gleeble-1500 thermal simulation testing machine, then the compression flow stress of the alloy was analyzed under the different deformation temperatures and strain rates. The relationship among the flow stress, the deformation temperatures and the strain rates was studied during hot deformation of AZ61 magnesium alloy, and the corresponding model of flow stress was established. The resuits showed that the flow stress increased with the strain rate increasing at the constant temperature, and the flow stress decreased with the deformation temperature increasing at the constant strain rate during the hot compression deformation of AZ61 magnesium alloy. The process of the hot deformation of AZ61 magnesium alloy had been characteristic of dynamic recrystallization all the time a little obviously, in which its flow stress was affected by the combination of work--hardening and dynamic recrystallization softening. It was indicated that during the hot compression, the peak value of flow stress of AZ61 magnesium alloy could be depicted by the hyperbolic-sine mathematical model preferably.

关 键 词：镁合金 热变形 流变应力 激活能 应变速率 

分 类 号：TG166.493[金属学及工艺—热处理]