Surface nanocrystallisation engineering: scientific and industrial potential

Abstract

By means of surface mechanical attrition treatment (SMAT), a nanostructured surface layer with a graded grain size distribution ranging from nano-to micrometres can be synthesised on various metallic materials. In this paper, the grain refinement mechanism, mechanical and diffusion properties, and chemical reactivity of the nanostructured surface layer, are reviewed. In addition, effects of the nanostructured surface layer on the mechanical performance and surface thermochemical treatment processes of engineering materials are described. Previous investigations have indicated that the nanostructured surface layer synthesised by means of SMAT on metallic materials provides many unique opportunities in both basic scientific research and technological applications.