交流電位差法による複数き裂検出法の開発

抄録

This paper studies the multiple crack detection by a. c. potential method. Alternating currents from 200 Hz to 5000 Hz were applied to artificially cracked specimens of Incone 1738 LC superalloy having 1-5 cracks with 50-500 μm depth, and a. c. potentials raised by the cracks were measured at respective frequencies. The potentials had a linear relationship against the frequency and the gradient and intercept of the relationship depended on the number of cracks and crack depth. A new a. c. method was proposed for determining the number of cracks and crack depth by utilizing the frequency dependency of the gradient and intercept. The frequency dependency of the gradient and intercept from FEM analysis agreed with the experiment results qualitatively.