Characterization of hot deformation behavior of as-extruded Mg–Gd–Y–Zn–Zr alloy

• Published in: Journal of alloys and compounds 2014-10, Vol.610, p.203-211
• Main Authors: Xia, Xiangsheng, Chen, Qiang, Li, Jianping, Shu, Dayu, Hu, Chuankai, Huang, Shuhai, Zhao, Zude
• Format: Article
• Language: English
• Subjects: Condensed matter: structure, mechanical and thermal properties; Deformation; Deformation and plasticity (including yield, ductility, and superplasticity); Exact sciences and technology; Hot compression; Hot working; Magnesium base alloys; Mathematical models; Mechanical and acoustical properties of condensed matter; Mechanical properties; Mechanical properties of solids; Mg–Gd–Y–Zn–Zr alloy; Microstructure; Optimization; Physics; Processing map; Strain rate; Stress strain curves; Stress-strain relationships
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2014.04.210

•Hot deformation behavior of as-extruded Mg–Gd–Y–Zn–Zr alloy was studied.•The hot deformation behavior was studied by processing maps.•The optimum parameters for hot working of the tested alloy were obtained.•Three components were successfully prepared according to the determined hot deformation parameters. The hot deformation characteristics of as-extruded Mg–Gd–Y–Zn–Zr alloy have been investigated by isothermal compression tests in the temperature range of 300–500°C and strain rate range of 0.001–1s−1. Several modeling approaches, including flow stress–strain curves, a constitutive Arrhenius type equation model and processing map were used to characterize the deformation behavior of as-extruded Mg–Gd–Y–Zn–Zr alloy in this study. In addition, isothermal precision forging of the component with complex shape was carried out to evaluate the optimum parameters for hot working of the alloy at elevated temperatures. The results show that the deformation activation energy of the experimental alloy was estimated to be 240.477kJ/mol, and the stress exponent was 3.899. The optimum parameters for hot working of the as-extruded Mg–Gd–Y–Zn–Zr alloy were deformation temperatures of 380–450°C and strain rates of 0.003–0.02s−1. According to the determined hot deformation parameters, three components were successfully prepared, and its possessed excellent surface quality, the ultimate tensile strength, yield strength and elongation of the component were 378MPa, 283MPa and 11.5%, respectively.