论文部分内容阅读
为了研究AZ31镁合金在热变形过程中的微观组织演变,将AZ31镁合金板料加工成微尺度拉伸试样,并采用自主研发、基于显微平台的微尺度构件多场耦合作用及测试装置,以10℃/min加热到250℃,保温5 min后以8×10-3 s-1应变速率进行拉伸,在光学显微镜下观测镁合金板材拉伸过程中的晶粒组织变化。结果表明:应变为8%时,晶粒出现“项链”结构形貌;应变为16%时,“项链晶”数量增加,主要出现在与拉伸方向成45°角位置;同时,孪晶组织出现。应变量为32.5%时,即断裂前,孪晶数量剧增,部分“项链晶”被替代,少量变形晶粒出现。显然,镁合金断裂与孪晶有很大的关系。
In order to study the microstructure evolution of AZ31 magnesium alloy during hot deformation, the AZ31 magnesium alloy sheet was processed into micro-scale tensile specimens and the multi-field coupling effect and testing device , Heated to 250 ° C at 10 ° C / min, stretched for 5 min at a strain rate of 8 × 10-3 s-1, and observed for grain structure changes during drawing of the magnesium alloy sheet under a light microscope. The results show that when the strain is 8%, the grains appear “necklace” structure morphology; when the strain is 16%, the number of “necklace crystal” increases, mainly in the angle of 45 ° with the stretching direction; , Twins appear. When the strain is 32.5%, that is, the number of twins increases sharply before the fracture, part of the “necklace” is replaced and a small amount of deformed grains appear. Obviously, magnesium alloy fracture and twins have a great relationship.