Temperature and Strain-Rate Dependence of the Flow Stress of AgMg Single Crystals

The effect of temperature and strain rate on the flow stress of β-AgMg single crystals was investigated in the temperature range of 77° to 900°K and strain-rate range of 10−4 to 104 sec−1. The low-temperature data were found to obey the predictions of the Peierls mechanism up to strain rates of 1.8×104 sec−1. Above strain rates of 1.8×104 sec−1 the shear stress becomes athermal and strain-rate-sensitive. The high-temperature data were found to be thermally activated and showed increasing strength with decreasing temperature and increasing strain rate. There is a temperature-sensitive, strain-rate-insensitive region which divides the low- and high-temperature thermally activated mechanisms and shows increasing strength with increasing temperature.