Thermal stability of grain structure and defects in submicrocrystalline and nanocrystalline nickel

The grain and defect structure of submicrocrystalline and nanocrystalline nickel produced by equichannel angular pressing or by ball milling, respectively, has been studied by isochronal and isothermal annealing experiments, and Xray investigations. A detailed analysis of the thermal stability of the di.erent types of microstructures will be presented.