STRESS-CORROSION CRACK INITIATION OF TYPE 304 STAINLESS STEEL IN ATMOSPHERIC ENVIRONMENTS CONTAINING CHLORIDE: INFLUENCE OF SURFACE CONDITION, RELATIVE HUMIDITY, TEMPERATURE AND THERMAL SENSITIZATION

摘要

Previous work by the present authors has described the influence of a range of variables on atmospheric chloride-induced stress corrosion initiation behavior of Type 304 stainless steels using polished C-rings. This paper extends the previous studies in order to establish the effect of surface condition on the initiation of SCC. Three machining conditions were utilized in this study, each using different machining combinations in terms of material removal, either by lathe turning or turning followed by grinding. These conditions all produced significantly greater crack initiation than was seen under the same conditions on polished specimens, although the ground surface condition had less effect than the other two. The results highlight the importance of surface condition in the initiation and prevention of SCC in plant.