A Study on Detecting Flaws Using DC Potential Drop Method

직류전위차법을 이용한 결함검출에 관한 연구

Bae, Bong-Guk;Seok, Chang-Seong

  • Published : 2000.04.01


In this paper, a DC potential drop measurement system was used to find the position of the flaw on a simple thin plate. Four-point probe test was evaluated and used for this study. In the four-point probe test, the more distance between current pins provides the more measurable scope, the less voltage difference, and the more voltage difference rate. In the other hand, the more distance between voltage pins provides the less voltage difference and the less voltage difference rate. An optimized four-point probe was applied to measure the relation between voltage and the relative position of flaw to the probe. The Maxwell 21) simulator was used to analyze the electromagnetic field, and it showed that the analytical result was similar to the experimental result within 11.4% maximum error.


DCPD;Four-Point Probe;Voltage Difference;Flaw;Contact Resistance


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