A numerical study of indentation with small spherical indenters

Jiang Qin, Shaoxing Qu, Xue Feng*, Yonggang Huang, Jianliang Xiao, Keh Chih Hwang

*Corresponding author for this work

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

The finite element method for the conventional theory of mechanism-based strain gradient plasticity is used to study the indentation size effect. For small indenters (e.g., radii on the order of 10 μm), the maximum allowable geometrically necessary dislocation (GND) density is introduced to cap the GND density such that the latter does not become unrealistically high. The numerical results agree well with the indentation hardness data of iridium. The GND density is much larger than the density of statistically stored dislocations (SSD) underneath the indenter, but this trend reverses away from the indenter. As the indentation depth (or equivalently, contact radius) increases, the GND density decreases but the SSD density increases.

Original languageEnglish (US)
Pages (from-to)18-26
Number of pages9
JournalActa Mechanica Solida Sinica
Volume22
Issue number1
DOIs
StatePublished - Feb 1 2009

Fingerprint

Indentation
Iridium
Plasticity
Hardness
Finite element method

Keywords

  • geometrically necessary dislocations
  • indentation size effect
  • maximum density
  • spherical indenters

ASJC Scopus subject areas

  • Mechanical Engineering
  • Computational Mechanics
  • Mechanics of Materials

Cite this

Qin, Jiang ; Qu, Shaoxing ; Feng, Xue ; Huang, Yonggang ; Xiao, Jianliang ; Hwang, Keh Chih. / A numerical study of indentation with small spherical indenters. In: Acta Mechanica Solida Sinica. 2009 ; Vol. 22, No. 1. pp. 18-26.
@article{3414d9f16f9b4d80bec09229f2a622bc,
title = "A numerical study of indentation with small spherical indenters",
abstract = "The finite element method for the conventional theory of mechanism-based strain gradient plasticity is used to study the indentation size effect. For small indenters (e.g., radii on the order of 10 μm), the maximum allowable geometrically necessary dislocation (GND) density is introduced to cap the GND density such that the latter does not become unrealistically high. The numerical results agree well with the indentation hardness data of iridium. The GND density is much larger than the density of statistically stored dislocations (SSD) underneath the indenter, but this trend reverses away from the indenter. As the indentation depth (or equivalently, contact radius) increases, the GND density decreases but the SSD density increases.",
keywords = "geometrically necessary dislocations, indentation size effect, maximum density, spherical indenters",
author = "Jiang Qin and Shaoxing Qu and Xue Feng and Yonggang Huang and Jianliang Xiao and Hwang, {Keh Chih}",
year = "2009",
month = "2",
day = "1",
doi = "10.1016/S0894-9166(09)60086-0",
language = "English (US)",
volume = "22",
pages = "18--26",
journal = "Acta Mechanica Solida Sinica",
issn = "0894-9166",
publisher = "Huazhong University of Science and Technology",
number = "1",

}

A numerical study of indentation with small spherical indenters. / Qin, Jiang; Qu, Shaoxing; Feng, Xue; Huang, Yonggang; Xiao, Jianliang; Hwang, Keh Chih.

In: Acta Mechanica Solida Sinica, Vol. 22, No. 1, 01.02.2009, p. 18-26.

Research output: Contribution to journalArticle

TY - JOUR

T1 - A numerical study of indentation with small spherical indenters

AU - Qin, Jiang

AU - Qu, Shaoxing

AU - Feng, Xue

AU - Huang, Yonggang

AU - Xiao, Jianliang

AU - Hwang, Keh Chih

PY - 2009/2/1

Y1 - 2009/2/1

N2 - The finite element method for the conventional theory of mechanism-based strain gradient plasticity is used to study the indentation size effect. For small indenters (e.g., radii on the order of 10 μm), the maximum allowable geometrically necessary dislocation (GND) density is introduced to cap the GND density such that the latter does not become unrealistically high. The numerical results agree well with the indentation hardness data of iridium. The GND density is much larger than the density of statistically stored dislocations (SSD) underneath the indenter, but this trend reverses away from the indenter. As the indentation depth (or equivalently, contact radius) increases, the GND density decreases but the SSD density increases.

AB - The finite element method for the conventional theory of mechanism-based strain gradient plasticity is used to study the indentation size effect. For small indenters (e.g., radii on the order of 10 μm), the maximum allowable geometrically necessary dislocation (GND) density is introduced to cap the GND density such that the latter does not become unrealistically high. The numerical results agree well with the indentation hardness data of iridium. The GND density is much larger than the density of statistically stored dislocations (SSD) underneath the indenter, but this trend reverses away from the indenter. As the indentation depth (or equivalently, contact radius) increases, the GND density decreases but the SSD density increases.

KW - geometrically necessary dislocations

KW - indentation size effect

KW - maximum density

KW - spherical indenters

UR - http://www.scopus.com/inward/record.url?scp=63149128173&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=63149128173&partnerID=8YFLogxK

U2 - 10.1016/S0894-9166(09)60086-0

DO - 10.1016/S0894-9166(09)60086-0

M3 - Article

VL - 22

SP - 18

EP - 26

JO - Acta Mechanica Solida Sinica

JF - Acta Mechanica Solida Sinica

SN - 0894-9166

IS - 1

ER -