Grain Size Variation during Low Temperature Creep and Tensile Deformation of Ultrafine-Grained Copper

Creep and tensile tests at temperatures between 298 and 393 K were conducted on ultrafine-grained (UFG) copper processed by equal channel angular pressing. Steady-state deformation appeared in all the test conditions. Grain size distribution and average grain size were measured by an electron backscatter diffraction technique before and after the mechanical tests. The steady-state deformation behavior and grain size variation were investigated. From these experimental results together with the measurement of the activation energy of deformation, deformation mechanisms of UFG copper are discussed.