Cryogenic fracture behaviors and polarization characteristics according to sensitizing heat treatment on structural material of the nuclear fusion reactor

핵 융합로 구조재료의 예민화 열처리에 따른 극저온 파괴거동 및 분극특성

Kwon, Il-Hyun;Chung, Se-Hi

  • Published : 1998.02.01


The cryogenic fracture behaviors of austenitic stainless steel HN2 developed for nuclear fusion reactor were evaluated quantitatively by using the small punch(SP) test. The electrochemical polarization test was applied to study thermal aging degradation of HN2 steel. The X-ray diffraction(XRD) analysis was conducted to detect carbides and nitrides precipitated on the grain boundary of the heat treated HN2 steel. The mechanical properties of the HN2 steel significantly decreased with increasing time and temperature of heat treatment or with decreasing testing temperature. The integrated charge(Q) obtained from electrochemical polarization test showed a good correlation with the SP energy(ESP) obtained by means of SP tests. From the results observed in the x-ray diffraction and anodic polarization curve, it was known that the material the grain boundary. Combining SP test and electrochemical polarization test, it could be useful tools to non-destructively evaluate the cryogenic fracture behaviors and the aging degradation for cryogenic structural material.


Cryogenic Fracture Behaviors;Nuclear Fusion Reactor;Small Punch Test;Electrochemical Polarization Test;Material Degradation;Anodic Polarization Curve;Integrated Charge;Sensitizing Heat Treatment