Detection of Hydrogen Damage in 2.25Cr1Mo0.25V by Ultrasonic Inspection

2.25Cr1Mo0.25V steel has better high temperature strength than ordinary Cr-Mo steel, and has been widely used in nuclear and chemical environments such as nuclear energy and chemical industry. However, vanadium-added steel is still likely to cause hydrogen damage and requires early detection. Ultrasonic inspection has strong penetrating ability. It can detect thin plates with thickness of 1-2mm and steel structure of several meters long. In this paper, ultrasonic longitudinal wave was used to detect the amplitude and longitudinal wave period before and after hydrogen charging, and the change of wave velocity was obtained. The dynamic tensile test of the specimen before and after hydrogen charging was also carried out, and the elastic modulus and elongation of hydrogen before and after hydrogen charging were obtained. The relationship between ultrasonic signal and hydrogen embrittlement was also discussed in this paper.