Instrumented indentation is a popular method for determining mechanical properties in engineering materials. However, there are several shortcomings and challenges involved with correctly interpreting the test results. We propose here a unified method for evaluating instrumented indentation testing conducted on a material that exhibits both strain hardening under yielding and which is subjected to uniform, equi-biaxial residual stresses. The proposed method is based on extensive finite element simulations that relate the parameter-space spanned by Young's modulus, yield strength, strain hardening and residual stress, to the response from the indentation test. Based on reverse analysis, the proposed method can be used to determine two unknown quantities, such as yield strength and strain hardening. The technique involves utilizing the concept of representative strain and plural indenter-shapes. © 2006 Elsevier Ltd. All rights reserved.
Bibliographical noteJ.Y. and A.M.K. acknowledge that this work was supported by ONR-N00014-04-1-0498 and NSF DMR-0346664. X.C. was supported by NSF CMS-0407743.
- Finite element analysis
- Representative strain
- Residual stress