0
Research Papers

A Method for Estimating Uncertainty of Indentation Tensile Properties in Instrumented Indentation Test

[+] Author and Article Information
Eun-chae Jeon

Division of Nano-Mechanical Systems, Korea Institute of Machinery & Materials, Daejeon, 305-343, Koreajeonec@kimm.re.kr

Joo-Seung Park

Technology & Standards Policy Division, Korea Agency for Technology and Standards, Gwacheon, 427-723, Koreajoospark@ats.go.kr

Doo-Sun Choi

Division of Nano-Mechanical Systems, Korea Institute of Machinery & Materials, Daejeon, 305-343, Koreachoids@kimm.re.kr

Kug-Hwan Kim

School of Materials Science and Engineering, Seoul National University, Seoul, 151-742, Koreasamadhi0@snu.ac.kr

Dongil Kwon

School of Materials Science and Engineering, Seoul National University, Seoul, 151-742, Koreadongilk@snu.ac.kr

J. Eng. Mater. Technol 131(3), 031006 (May 26, 2009) (6 pages) doi:10.1115/1.3120391 History: Received September 11, 2008; Revised February 04, 2009; Published May 26, 2009

The instrumented indentation test, which measures indentation tensile properties, has attracted interest recently because this test can replace uniaxial tensile test. An international standard for instrumented indentation test has been recently legislated. However, the uncertainty of the indentation tensile properties has never been estimated. The indentation tensile properties cannot be obtained directly from experimental raw data as can the Brinell hardness, which makes estimation of the uncertainty difficult. The simplifying uncertainty estimation model for the indentation tensile properties proposed here overcomes this problem. Though the influence quantities are generally defined by experimental variances when estimating uncertainty, here they are obtained by calculation from indentation load-depth curves. This model was verified by round-robin test with several institutions. The average uncertainties were estimated as 18.9% and 9.8% for the indentation yield strength and indentation tensile strength, respectively. The values were independent of the materials’ mechanical properties but varied with environmental conditions such as experimental instruments and operators. The uncertainties for the indentation yield and tensile strengths were greater than those for the uniaxial tensile test. These larger uncertainties were caused by measuring local properties in the instrumented indentation test. The two tests had the same tendency to have smaller uncertainties for tensile strength than yield strength. These results suggest that the simplified model can be used to estimate the uncertainty in indentation tensile properties.

FIGURES IN THIS ARTICLE
<>
Copyright © 2009 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 1

Schematic of material deformation around a spherical indenter

Grahic Jump Location
Figure 2

Five indentation load-depth curves for S45C steel from KEPRI

Grahic Jump Location
Figure 3

Regression analysis of uncertainties with (a) indentation yield strength and (b) indentation tensile strength

Grahic Jump Location
Figure 4

Variation in uncertainties from the five institutions

Grahic Jump Location
Figure 5

General example of uniaxial tensile curves

Grahic Jump Location
Figure 6

Differential values of true stress of tensile curve

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In