高周波超音波を用いたW-Cu固相接合界面検査技術の検討
概要
This study evaluated the applicability of high-frequency ultrasonic testing to the inspection of W-Cu bonded interface aiming at the development of a non-destructive testing technique for the inspection of the cooling channel of the divertor of a fusion reactor. Tungsten blocks measuring approximately 30×30×13 mm were bonded with oxygen-free copper blocks using a high temperature vacuum furnace with uniaxial pressure and the thickness of the oxygen-free copper blocks was reduced to 2.5 mm. Artificial grooves were machined to some of the tungsten blocks to introduce artificial delamination at the bonded interface. Subsequent immersion ultrasonic inspections were carried out using a 30 MHz transducer. The results of the inspections provided C-scan images clearly showing the artificial grooves with a diameter of 1 mm.
