Prediction of the Reduction in J-R Curve of Stainless Steel Weld with Thermal Embrittlement Using Micro-indentation Test

마이크로 압입 시험을 이용한 용접 스테인리스강의 열취화에 따른 J-R 곡선 저하 예측

In this paper, a method to quantitatively predict the reduction in fracture resistance with thermal embrittlement using micro indentation test. The change in hardness of δ-ferrite with thermal embrittlement is characterized using a concept of hardening constant. Then, thermal embrittlement constant to predict the reduction in fracture resistance with thermal embrittlement is derived from the relation between hardening constant and thermal embrittlement constant. Finally, the reduction in fracture resistance with thermal embrittlement is predicted by multiplying thermal embrittlement constant obtained from micro indentation test by J-R curve of unaged material. The validity of the hardening constant concept is confirmed by comparing the prediction and experimental results.