Journal of Mechanical Science and Technology

The Korean Society of Mechanical Engineers (대한기계학회)
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A Comparative Evaluation of $K_{op}$ Determination and $\Delta{K}_{eff}$ Estimation Methods

  • Kang, Jae-Youn (Korea Institute of Machinery ＆ Materials,) ;
  • Song, Ji-Ho (Department of Automation and Design Engineering, Korea Advanced Institute of Science and Technolog) ;
  • Koo, Ja-Suk (Department of Automation and Design Engineering, Korea Advanced Institute of Science and Technolog) ;
  • Park, Byung-Ik (Korea Institute of Machinery ＆ Materials)
  • Published : 2004.06.01
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Abstract

Methods for determination of the crack opening stress intensity factor ($K_{op}$) and for estimation of the effective stress intensity factor range ($\Delta{K}_{eff}$) are evaluated for crack growth test data of aluminum alloys. Three methods of determining $K_{op}$, visual measurement, ASTM offset compliance method, and the neural network method proposed by Kang and Song, and three methods of estimating $\Delta{K}_{eff}$, conventional, the 2/PIO and 2/PI methods proposed by Donald and Paris, are compared in a quantitative manner by using evaluation criteria. For all $K_{op}$ determination methods discussed, the 2/PI method of estimating $\Delta{K}_{eff}$ provides good results. The neural network method of determining $K_{op}$ provides good correlation of crack growth data. It is recommended to use 2/PI estimation with the neural $K_{op}$ determination method. The ASTM offset method used in conjunction with 2/PI estimation shows a possibility of successful application. It is desired to improve the ASTM method.

Keywords

References

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