Mechanism of Stress Corrosion Cracking in SUS 304 Duplex Weld Metal

概要

論文の詳細を見る
Stress corrosion cracking (SCC) tests were conducted in 42% MgCi_2 aq. solution (143゜C) on SUS 304 stainless steel weld metals which exhibitedδ+γ duplex phase structure. Content ofδ-ferrite was varied by heat treatment. Results are as follows. The SCC growth rate in duplex weld metals is found to be delayed by δ-ferrite contained. Generally, this phenomena is called "Keying effect". Electro-chemical measurements are performed by, potentiostatic method to clarify the mechanism of keying effect. As natural electorode potential (NEP) of δ-ferrite is less noble than that of austenite phase, the dissolution of δ-ferrite is promoted by coupling with austenite phase and a dissolution of austenite phase is prevented under the influence of cathodic protection from δ-ferrite phase. It is likely that a remarkable dissolution of δ-ferrite would intercept the SCC growth in δ-ferrite and the SCC growth in austenite phase would be delayed due to cathodic protection frorn δ-ferrite to austenite phase.
社団法人溶接学会の論文
1984-04-01