Development of the DCPD Method Based on Finite Element Analysis for Measuring Semi-Elliptical Surface Cracks

반타원 표면균열 형상측정을 위한 유한요소 전기장 해석에 기초한 직류전위차법의 개발

  • Published : 2001.07.01


One of major problems in analyzing failure mechanism of real components is the accurate measurement of crack size and shape. The DCPD(Direct Current Potential Drop) method has been widely used for the crack measurement of a structure and finite element analysis has been used for the derivation of calibration equations, which relates the potential drop with the crack depth. In this paper, finite element analyses were performed for semi-elliptical surface cracks with various crack shapes(a/c) and crack depths(a/t). As a result, a calibration equation has been derived for the measurement of a semi-elliptical surface crack in wide plates. Analytical results are compared with experimental results to evaluate the validity and the applicability of the derived equation. The proposed method is expected to provide efficient and accurate measurement of a surface crack during crack growth.


DCPD Method;Finite Element Analysis;Surface Crack;Crack Configuration Measurement


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