About notch effect on the environment sensitivity of high-tensile steels

In order to elucidate the main cause of delayed brittle fracture of high-strength steels with a rigid concentrator under combined effect of tensile stresses and neutral solutions, pre-fracture time vs. level of applied tensile stresses dependence curves have been plotted for notched and unnotched samples of steels 30KhGSNA and EI-643 in tap water. On the basis of the electrochemical behaviour and the functional sigma - tau dependence analysis data it is established that notched samples of steels 30KhGSNA and EI-643 are subject to delayed brittle fracture in tap water, which proceeds by the hydrogen brittleness mechanism