CAJ | 학술논문

在室温条件下，对国产压水堆核电站主管道母材及其TIG 接头试样进行疲劳裂纹扩展试验，并采用光学显微镜观测裂纹扩展路径，结合扫描电镜观察试样断口微观形貌。试验结果显示TIG接头的裂纹扩展速率高于母材，基于简化的四参数全范围 Forman 模型可以表征主管道母材与焊材全范围的疲劳裂纹扩展规律。疲劳裂纹在奥氏体与铁素体相内主要呈穿晶扩展，但在部分区域裂纹沿α/α或α/γ相界产生分支。
재실온조건하，대국산압수퇴핵전참주관도모재급기TIG 접두시양진행피로렬문확전시험，병채용광학현미경관측렬문확전로경，결합소묘전경관찰시양단구미관형모。시험결과현시TIG접두적렬문확전속솔고우모재，기우간화적사삼수전범위 Forman 모형가이표정주관도모재여한재전범위적피로렬문확전규률。피로렬문재오씨체여철소체상내주요정천정확전，단재부분구역렬문연α/α혹α/γ상계산생분지。
A series of fatigue crack growth rate tests were carried out on the primary pipe of the pressurized water reactor nuclear power plant at room temperature, the research objects include base material and its TIG welded joint specimens. The fatigue crack growth rate was measured, and the crack propagation path was observed using an optical microscope.Furthermore, the sample fracture morphology was analyzed with a scanning electron microscope. The crack-growth curve identify that the crack growth rate of TIG welded joint specimen is higher than the base material. It is found that the Forman model can be used to describe the crack growth behavior for two materials. The crack predominantly shows a transgranular mode, but branch crack along the α/αorα/γphase boundary was observed in the crack growth area.