Ultrasonic Creeping Wave Test Technique for Dissimilar Metal Weld

To solve the problem encountered in the defect inspection of the surface and near-surface of dissimilar metal weld effectively, a new ultrasonic creeping wave test technique is developed. In this paper, the test technique and its experimental verification are mainly described. The verification results show that linear defect, which is similar to the defect found in liquid penetrant test, on the surface and near-surface of dissimilar metal weld can be detected effectively, by using ultrasonic creeping wave test technique. And the depth, length and height of the defect can be determined easily. The effective covering depth of ultrasonic creeping wave test technique will reach 0-9mm. Meanwhile, the planar defect, with equivalent area more than 3mm², existed in welds can be detected efficiently. So, accurate measurement, which self height dimension of planar defect is above 2mm, will be realized.