비등 40% MgCl_2 용액에서 22Cr5Ni2Mo 2상 스테인리스강 용접재의 응력부식균열 특성 = Stress Corrosion Cracking of 22Cr5Ni2Mo Duplex Stainless Steel Weldment in Boiling 40% MgCl_2 Solution

다국어 초록 (Multilingual Abstract)

The microstructure and stress corrosion cracking behaviors in 22Cr5Ni2Mo suplex stainless steel weldment have been investigated. The SCC has been examined in terms of relevant electrochemical parameters in boiling 40% MgCl₂solution. The austenite content of the weld metal had twice as much as that of the base metal due to the effect of additive elements Ni, N and reheat effect by the multipass welding. The steel had the threshold stress of 29.1 kg/㎟ and the critical cracking potencial(E_CC) of -410mV immune to the SCC, and possessed superior SCC resistance compared to the austennitic stainless steel. Above the E_cc the SCC of the weldment occurred at the base metal regardless of the welding method. Cracks were initiated and propagated transgranularly without retarding effect by the phase the austenite phase in high stress region.