오스테나이트계 스테인리스 주강에서 합금원소가 크랙에 미치는 영향

Effects on the Crack of the Alloy Elements in Austenitic Stainless Cast Steels

The effects on the crack of alloy elements in austenitic stainless cast steels were investigated by utilizing microscope, SEM(scanning electron microscopy) and EDS(energy dispersive x-ray spectroscopy). In fractography, they observed cleavage fracture as brittle fracture before motoring test and intergranular fracture as fatigure crack after motoring test, and then NbC carbide observed in crack initiation after motoring test. In crack growth behavior, crack propagation were progress along with MnS and M23C6 etc carbides after motoring test. Carbide Volume fraction, like Cr-rich M23C6, M(C), increase and M3P occurred around MnS more than before motoring test.