Experimental Mechanics

, Volume 38, Issue 1, pp 13–17 | Cite as

Quantitative metallographic study for evaluation of fracture strain

  • M. Ohashi


A new method was developed for estimating fracture strain by measuring the aspect ratio of the ferrite grains. The method provides an appropriate estimate of the fracture strain of a notched specimen with different notch acuity. The average aspect ratio immediately underneath the fracture surface was used to deduce the fracture strain by means of the calibration curve established from a metallographic examination on the unnotched specimen. The estimated fracture strains were found to be in reasonably good agreement with the measured values within a margin of error of 10 percent. As such, it can be said that the method presented here could be a useful technique for providing an appropriate estimate of the fracture strain of a mechanical component.


Ferrite Mechanical Engineer Aspect Ratio Calibration Curve Fracture Surface 
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Copyright information

© Society for Experimental Mechanics, Inc. 1998

Authors and Affiliations

  • M. Ohashi
    • 1
  1. 1.National Research Institute of Police ScienceTokyoJapan

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