Forming limits of magnesium alloy AZ31B sheet at elevated temperatures
Forming limits of magnesium alloy AZ31B sheet at elevated temperatures
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镁合金AZ31B板材高温成形极限
DOI：
10.1016/j.ijplas.2020.102822
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发表时间：
2020
影响因子：
9.8
通讯作者：
Wu Peidong
中科院分区：
文献类型：
--
作者：
Li Zihan;Zhou Guowei;Li Dayong;Jain Mukesh K.;Peng Yinghong;Wu Peidong
镁合金板材通常需要进行温成形，变形路径的改变和组织演变对其温成形性能有着重要的影响。设计并实现了变形路径变化条件下AZ 31 B镁合金板材的成形极限试验，研究了变形路径和微观组织演变对成形极限图的影响。在150 °C、200 °C和300 °C下，在平面内单轴、平面应变和双轴拉伸加载路径下对片材进行预应变，然后在三个温度下使用从预应变样品中提取的试样进行半球形冲压拉伸实验。将动态再结晶（DRX）和退火回复的晶体塑性模型与Marciniak-Kuczyplaski（M-K）方法相结合来计算FLD。对200 °C预应变FLD试验中退火过程中位错密度的演变进行了评估，通过该评估，预应变FLD的预测得到了相当大的改善。本工作提供了实验以及晶体塑性为基础的方法来评估温度，预应变，动态再结晶和恢复影响的镁合金温成形性。
Magnesium alloy sheets usually has to be processed by warm forming, and change of strain path and evolution of microstructure can significantly influence their warm formability. Forming limit test for an AZ31B alloy sheet under strain path changes was configured and implemented, and the effects of strain paths and microstructure evolution on the forming limit diagram are investigated. The sheet was pre-strained under in-plane uniaxial, plane strain and biaxial tension loading paths at 150 °C, 200 °C and 300 °C, followed by hemispherical punch stretching experiments at the three temperatures using specimens extracted from the pre-strained samples. A crystal plasticity model that incorporates dynamic recrystallization (DRX) and annealing recovery was combined with the Marciniak-Kuczyński (M-K) approach to calculate the FLDs. The evolution of dislocation density during annealing in the pre-strained FLD test at 200 °C was evaluated, through which the predictions of pre-strained FLDs were considerably improved. The present work provides experimental as well as crystal plasticity based methods for evaluating warm formability of magnesium alloys influenced by temperature, pre-straining, DRX and recovery.