Compression Deformation Mechanisms of Nanocrystalline Ni Prepared by Plasma Evaporation Method

To investigate mechanical behaviors and deformation mechanisms of nanocrystalline materials, bulk nanocrystalline Ni samples were prepared by a plasma evaporation method combined with hot pressure sintering. The compressive mechanical properties of the bulk samples were tested under different quasi-static strain rates at room temperatures, and the evolution of the microstructure of the bulk sample before and after compression was studied. Results indicate that the bulk samples show a good combination of strength and ductility during the compressive testing. Meanwhile, the grain size of the compressed sample decreases compared with that of the sintered sample, while the microstrain of the grain increases after compression. Based on experimental results, it is can be inferred that both grain boundary dislocation glide and grain boundary sliding are the main deformation mechanisms for the bulk NC Ni samples.