A physical model revealing strong strain hardening in nano-grained metals induced by grain size gradient structure

Jianjun Li, Shaohua Chen, Xiaolei Wu, Ai Kah Soh

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54 Citations (Scopus)


A theoretical model has been developed, which reveals the underlying correlation between the strong extra strain hardening achieved in the nano-grained layers of the grain size gradient structure and the non-uniform deformation of the lateral surface in surface nano-crystallized materials, based on some existing experimental observations and the concept of geometrically necessary dislocations. The proposed model led to the establishment of a simple physical law that can be expressed as H*=A*, where H* and A* are two dimensionless parameters. The former represents the extra strain hardening, while the latter characterizes the non-uniform deformation of the lateral surface. The values of these two parameters can be measured through experiments.
Original languageEnglish
Pages (from-to)16 - 21
Number of pages6
JournalMaterials Science and Engineering A: Structural Materials: Properties, Microstructure and Processing
Issue numberJanuary 2015
Publication statusPublished - 2015

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