평균 응력 삼축비와 로드각이 저온용 고장력강(EH36)의 파단에 미치는 영향 분석

초록

Stress triaxiailty and lode angle have been considered as important factors for prediction of failure strain of ductile metals. This study deals with failure strain formulation according to the average stress triaxiality and lode angle for a typical ice class steel, EH36. A number of tests are performed on asymmetric flat notch specimens which each covers intermediate high stress triaxiality and lode angle zones. Numerical simulation of each specimen is carried out to identify stress fields and failure strain at fracture location using commercial finite element code, Abaqus.Standard. In detail, the location of failure in numerical simulations are identified from a comparison of engineering stress vs. strain curves with experimental ones. The failure strain curves of EH36 steel are newly roposed as a function of two variables: the stress triaxiality and the lode angle.