FACTORS INFLUENCING STRESS-CORROSION CRACKING OF HIGH-STRENGTH PEARLITIC STEELS

In this paper the main variables which affect stress corrosion cracking (SCC) of high strength pearlitic steels are analysed from the fracture mechanics point of view. To this end, slow strain rate tests (SSRTs) and constant strain tests (CSTs) under various mechanical and electrochemical conditions were carried out on pre-packed and notched samples of two high strength pearlitic steels, thus allowing a study of the influence of electrochemical variables such as the pH of the solution and the electrochemical potential, mechanical variables as the maximum stress intensity factor during fatigue pre-cracking (in pre-cracked samples) and the displacement rate applied to the sample ends, and geometric variables as the notch geometry (in notched samples) which determines the stress state in the vicinity of the notch tip and therefore controls the environmentally induced fracture process.