Experimental Mechanics

, Volume 26, Issue 4, pp 379–385 | Cite as

Analysis of elastic-plastic ball indentation to measure strength of high-strength steels

  • J. H. Underwood
  • G. P. O'Hara
  • J. J. Zalinka
Article

Abstract

Ball-indentation experiment ware performed with A723 steel of 100- to 1200-MPa ultimate strength. Results are compared with conventional tension tests and with an elastic-plastic finite-element model of the ball indentation. Finite-element analysis shows the ball-indentation process to be insensitive to friction effects. Comparison of indentation and conventional tests shows that slip-line field analysis closely predicts the ball contact stress. The indentation tests gave an accurate measure of ultimate tensile strength because of the following test procedures: using a large ball size and a fixed ratio of indentation depth to ball size; accounting for directional material properties; accounting for extraneous system deflections.

Keywords

Ultimate Tensile Strength Indentation Depth Indentation Test Large Ball A723 Steel 

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Copyright information

© Society for Experimental Mechanics, Inc. 1986

Authors and Affiliations

  • J. H. Underwood
    • 1
  • G. P. O'Hara
    • 1
  • J. J. Zalinka
    • 1
  1. 1.Army Armament Research Development and Engineering CenterCCB-RMWatervliet

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