Plastic deformation characteristics of an Mg–3Al–1Zn alloy at low temperatures. (15th February 2016) - Wang, Hao
Abstract: Low temperature tension behavior of an Mg–3Al–1Zn alloy is evaluated at the strain rates of 10 − 2 /s, 10 − 3 /s and 10 − 4 /s, respectively. Within a test temperature range from 300 K to 77 K, the work hardening behavior and strain rate sensitivity of the examined alloy are characterized to reveal the plastic deformation mechanism varying with temperature from the point view of dislocation motion. With the observation of high initial work-hardening rate, high strain rate sensitivity and low activation volume at cryogenic temperatures, the dominated mechanism of dislocation motion is regarded as varying from dislocation interacting with forest dislocation above 173 K, into overcoming lattice fraction below 173 K, especially when deformed at 77 K. Graphical abstract: Highlights: Low temperature deformation characters of Mg-3Al-1Zn alloy was investigated. Deformation mechanism transition at low temperature was found to occur around 173 K for Mg-3Al-1Zn alloy. Dislocation interaction with lattice resistance was considered as main source for WH and SRS change below 173 K.