K4 Corrosion Fatigue Behavior of 12 Pct Chromium Stainless Steel for Steam Turbine Moving Blade

Abstract

In this paper characteristics of corrosion fatigue failures of steam turbine blades learned from failure analysis are briefly summarized. Then influencing variables on corrosion fatigue crack initiation and propagation process of 12 pct chromium stainless steel are briefly reviewed. The emphasis is focused upon initiation and propagation of corrosion pit in corrosion fatigue crack initiation process. Recent investigation of early stage of corrosion pit initiation process by use of electrochemical noise method is demonstrated. Finally future problems should be solved in corrosion fatigue crack initiation and propagation process of 12 pct chromium stainless steel are touched on briefly.