Determination of uniaxial residual stress and mechanical properties by instrumented indentation

TLDR: In this paper, an improved technique was proposed to determine the uniaxial residual stress, elastic modulus, and yield stress of a linear elastic, perfectly plastic bulk material from the force-displacement curve of one conical indentation test.

About: This article is published in Acta Materialia.The article was published on 2006-06-01 and is currently open access. It has received 84 citations till now. The article focuses on the topics: Indentation & Residual stress.

Figures

Fig. 4. Fitting surfaces of the three dimensionless equations (4)–(6), where the black dots represent the indentation data obtained from FEM simulations.

Fig. 8. (a) SEM image of indentation impressions on the cross-section of bond coat. (b) The indentation load–depth curve of the sixth impression (solid line), which agrees well with the numerical indentation load–depth curve using the material properties identified from the reverse analysis.

Fig. 1. Schematic of instrumented indentation with a conical indenter. (a) Normal indentation on the topcoat and cross-section indentation on the bond coat of a thermal barrier system. (b) As long as the impression is small, the cross-section indentation may be modeled as an impression on a semi-infinite bulk with uniaxial residual stress. (c) Side view of conical indentation on a specimen with uniaxial in-plane residual stress. (d) Typical indentation depth– load curves obtained from an indentation experiment with loading work and unloading work indicated as the areas enclosed by the curve triangles.

Fig. 5. The flow chart for determining material properties and uniaxial residual stress using the reverse analysis.

Fig. 6. Comparison between the input material combinations used in FEM indentation experiments (end of arrow) and the material combinations identified from the reverse analysis (tip of arrow).

Fig. 3. Indentation depth–load curve obtained from FEM indentation test: (a) rres/rY varies from -1.0 to 1.0 with E/rY = 75; (b) E/rY varies from 10 to 1000 with rres/rY = -0.6.