Origin of lattice strain in nanocrystalline materials

Abstract

A striking feature of nanocrystalline (NC) materials prepared by different techniques is the variation of lattice strain present in the crystallites. A simple model is proposed to account for this phenomenon, which allows the establishment of a quantitative relationship describing the dependence of the crystal lattice strain on the grain size. Good agreement between theoretical and experimental data indicates that the stress field, induced by the excess volume in grain boundaries, is the dominant source of the lattice strain.

Acknowledgements

W. Qin is greatly indebted to Professor Y. W. Du (Nanjing University, China), Professor Z. H. Chen (Hunan University, China), Professor P. Y. Huang (Central South University, China) and Professor Y. H. Zhuang (Guangxi University, PR China) for helpful discussions and encouragement during this work.