Mechanical behavior of nanocrystalline copper

The mechanical behavior of nanocrystalline materials has been studied extensively for the past few years. Recent studies on artifact-free materials with nanosize grains less than 100 nm have been very fruitful. These nanograined metals have exhibited very high strengths with reasonably good ductility. While there have been a large number of studies on hardness and strength characteristics, studies on strain rate sensitivity (SRS) are very limited. We describe here some of our recent work in characterizing SRS as well as activation volumes of nanograined copper using different testing procedures. These tests have been carried out under iso-strain rate and iso-structural conditions.