Cylindrical nano-indentation on metal film/elastic substrate system with discrete dislocation plasticity analysis: A simple model for nano-indentation size effect

INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES

卷:47

Article

Ouyang, Chaojun^1,3  Li, Zhenhuan^1,2  Huang, Minsheng^1,2  Fan, Haidong^1,2 

[1] Huazhong Univ Sci & Technol, Dept Mech, Wuhan 430074, Peoples R China

[2] Hubei Key Lab Engn Struct Anal & Safety Assessmen, Wuhan 430074, Peoples R China

[3] CAS, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China

关键词: Film/substrate system;    Indentation size effect;    Discrete dislocation plasticity;    Cylindrical indenter;    Geometrically necessary dislocation;   

DOI  :  10.1016/j.ijsolstr.2010.07.012

来源: Elsevier

【 摘 要 】

The cylindrical nano-indentation on metal film/elastic substrate is computationally studied using two-dimensional discrete dislocation plasticity combined with the commercial software ANSYS (R), with a focus on the storage volume for geometrically necessary dislocations (GNDs) inside the films and the nano-indentation size effect (NISE). Our calculations show that almost all GNDs are stored in a rectangular area determined by the film thickness and the actual contact width. The variations of indentation contact width with indentation depth for various film thicknesses and indenter radii are fitted by an exponential relation, and then the GND density underneath the indenter is estimated. Based on the Taylor dislocation model and Tabor formula, a simple model for the dependence of the nano-indentation hardness of the film/substrate system on the indentation depth, the indenter radius and the film thickness is established, showing a good agreement with the present numerical results. (C) 2010 Published by Elsevier Ltd.

【 授权许可】

Free