Quantitative metallographic study for evaluation of fracture strain
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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.
KeywordsFerrite Mechanical Engineer Aspect Ratio Calibration Curve Fracture Surface
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