Room-temperature creep of nanocrystalline materials: a nanoindentation study

Abstract

Due to their extremely high volume fraction of grain boundaries, nanocrystalline materials are often expected to show the creep behavior at room temperature rather than normal dislocation-slip-dominant deformation. Here we investigated the room-temperature creep behavior of nanocrystalline materials through nanoindentation experiments. During nanoindentation tests, the load was increased up to various peak loads (10 ~ 200 mN) under different loading rates (0.1 ~ 2.5 mN/s) and then hold for 400 sec. Results are discussed in terms of the influence of the peak load and the loading rate on the room-temperature creep of nanocrystalline materials.