Indentation size effects on the strain rate sensitivity of nanocrystalline Ni-25at.%Al thin films

Nanoindentation creep tests on nanocrystalline Ni-25at.%Al thin films with a range of grain sizes in the nanometer range show the measured stress exponent to increase with indent size. At the same indent size, the as-deposited sample with smaller grain size exhibits higher strain rate sensitivity than the annealed samples with larger grain sizes.