Constitutive Modeling and Hot Deformation Behavior of Duplex Structured Mg-Li-Al-Sr Alloy

• Published in: Journal of materials science & technology Vol. 32; no. 12; pp. 1289 - 1296
• Main Authors: Yang, Yan, Peng, Xiaodong, Ren, Fengjuan, Wen, Haiming, Su, Junfei, Xie, Weidong
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-12-2016
• Subjects: Constitutive equation; Dynamic recrystallization; Hot deformation; Mg–Li alloys; Processing maps; 双相结构; 变形计算; 复式结构; 本构模型; 流动行为; 热压缩试验; 热变形行为; 铝锶合金; Hot deformation; Constitutive equation; Mg–Li alloys; Processing maps; Dynamic recrystallization
• ISSN: 1005-0302; 1941-1162
• DOI: 10.1016/j.jmst.2016.11.015

Hot deformation behavior of an as-extruded duplex structured Mg-9Li-3Al-2.5Sr alloy is investigated via hot compression tests conducted at 200-350℃ with strain rate of 0.001-1 s^-1.The flow behavior of Mg-9Li-3Al-2.5Sr alloy can be described accurately by hyperbolic sine constitutive equation and the average activation energy for deformation is calculated as 143.5 k J/mol.Based on a dynamic materials model,the processing maps of Mg-9Li-3Al-2.5Sr alloy which describe the variation of power dissipation efficiency are constructed as a function of temperature and strain rate.The processing maps exhibit an area of discontinuous dynamic recrystallization occurring at 280-300℃ with strain rate of 0.001-0.01 s^-1,which corresponds to the optimum hot working conditions.