Investigation of stress corrosion cracking in mild steel stainless steel and brass by stress relaxation technique

The paper substantiates the experimental evidences in favour of a model of stress activated anodic dissolution primarily through line defects as the initial step for the development of stress corrosion cracking. The experimental details and microstructural informations in the initial step of the cracking for mild steel, austenitic stainless steel and alpha brass in appropriate environments are reported. The possible role of the surface films in the initiation stage has been discussed and compared with the results obtained in different laboratories. Finally some of the general observations in different systems have been explained from the present findings. (S.B. Choudhury is at present with OCRI, D.T.D and P (Air), Koraput, Orissa, P.S. Nag and Z.H. Khan are with National Metallurgical Laboratory)