High-temperature tensile tests and activation volume measurement of free-standing submicron Al films

Abstract

Tensile tests on free-standing, 200-nm-thick Al films were conducted between room temperature and 200 °C. Applied strain rates were in the range 1×10−8–2×10−6/s. At a temperature of 200 °C a saturation of the flow stress was observed. The strain required to achieve steady-state saturation is of the order of 2×10−3, which is much smaller than for bulk Al. From the observed strain rate sensitivity of the saturation stress we calculate an activation volume Ωact=60b3, which is small compared to the value of 700b3 observed in bulk Al (b is the magnitude of Burgers vector).