Fe-Cr-Ni 오스테나이트계 스테인리스강의 미소편석과 잔류 δ-페라이트 양에 대한 계산 = Calculation of Microsegregation and Amount of Retained δ-ferrite in Fe-Cr-Ni Austenitic Stainless Steel

다국어 초록 (Multilingual Abstract)

In equilibrium, 304 stainless steel has only γ-austenite phase below about 1170℃ and solutes are uniformly distributed in γ-austenite. Due to incomplete solid-state diffusion, it has retained δ-ferrite as well as γ-austenite and the solute distribution becomes inhomogeneous in each phase. To further understand the solidification behavior of 304 stainless steel, the variation of δ-ferrite amount with temperature and the solute concentration in each phase across the phase boundary are calculated in this study. The calculated solute contents at the interface are in good agreement with experimental data available. It is shown that the equilibrium calculation using 304 steel composition itself produces better results than using equivalent composition. The calculated amounts of retained δ-ferrite using 304 equivalent composition are somewhat higher than experimentally observed values. Much better agreement between calculation results and experimental data is expected if more reliable experimental data can be obtained.