Investigation on the possibility of using the microshear test as a surveillance method to estimate the mechanical properties and fracture toughness of nuclear pressure vessel steel; A508CL3, and its joints welded by narrow-gap submerged-arc welding

摘要

The present paper has investigated the mechanical properties of nuclear pressure vessel steel, A508CL3, and its welded joints by using the microshear test method, and the fracture toughness of A508CL3 steel and its welds has also been estimated.Moreover, a comparison has been carried out between the conventional test, microshear test and fracture mechanics test. In addition, the possibility of using the microshear test on the surveillance program of nuclear pressure vessel embrittlement due toneutron irradiation has also been considered in detail, and the results indicate that the microshear test can be used successfully to estimate the degradation of mechanical properties both for A508CL3 steel and its welded joints. It has been found thatthe lower the microshear toughness, the smaller the Charpy V-notch (CVN) impact toughness and fracture toughness, as well as the tearing modulus. Finally, the results show that the microshear test method may be developed as a supplemental test method orstandard of ASTM E185 and E636.