Hot Deformation Behavior and Microstructural Evolution of Mg-Nd-Zn-Zr Magnesium Alloy

Abstract:

The hot deformation behaviors and microstructural evolution of Mg-3.0Nd-0.2Zn-0.4Zr (wt. %, NZ30K) alloy were investigated by means of the isothermal hot compression tests at temperatures of 350-500 °C with strain rates of 0.001, 0.01, 0.1 and 1s^-1. The results showed that the flow stress increased to a peak and then decreased which showed a dynamic flow softening. The flow stress behavior was described by the hyperbolic sine constitutive equation with an average activation energy of 193.8 kJ/mol. The average size of dynamically recrystallized grains of hot deformed NZ30K alloy was reduced by increasing the strain rate and/or decreasing the deformation temperature. A large amount of fine particles precipitated in the grains interior and at the grain boundaries when heated to the compression temperatures and soaked for 5min below 450 °C. However, the volume fraction of particles decreased significantly when soaked for 5 min at 500 °C, and the coarse particles precipitated mainly at the grain boundaries. Hot deformation at the temperature of 500 °C around and at the strain rate range of 0.1s^-1 was desirable for NZ30K alloy.

• Periodical: Materials Science Forum (Volumes 747-748)
• Pages: 320-326
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.747-748.320
• Online since: February 2013
• Authors: Wen Xiang Wu, Li Jin, Jie Dong, Zhen Yan Zhang, Wen Jiang Ding
• Keywords: Hot Compression Deformation, Microstructural Evolution, NZ30K Alloy, Precipitate

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