超音波干渉を用いた二次元内面分岐きずの非破壊測定

抄録

A new method is proposed to detect a branched planar flaw on the back surface of a plate using the interference of ultrasonic waves. Parameters for flaw evaluation are developed and examined through experimental results for artificial flaws. The way to distinguish a tilted flaw and a branched flaw is proposed using a parameter which shows the rate of decrement in the center peak amplitude of the interference fringe. The effect of tilt angle of the flaw on parameter, which indicates the amount of asymmetry of the interference fringe along the direction normal to the flaw, is investigated. Tilted angle larger than 5 degree can be identified from the tilted flaws using the present method with a branch angle of 10 from the normal direction of the inspection surface.