Using Radioactive Tracers to Study Chloride Stress Corrosion Cracking of Stainless Steels

Abstract

Abstract A combination of radioactive tracer and metallurgical techniques has made it possible to study some of the conditions necessary to produce chloride stress corrosion cracks in stainless steel The existence of charged areas on the surface of steel was demonstrated by autoradiography of samples exposed to solutions containing radioactive tracers. Charged areas on the surface may be created by a high concentration of small sulfide inclusions; the cracks that appeared were initiated within these charged areas. Seven nanograms of chloride on one charged area was sufficient to start corrosion and subsequent surface cracks in a surface of steel stressed by grinding.