Procedure of the study of initial stage of delayed fracture of the metal of HAZ of high-strength low-alloyed steel welded joints

摘要

The procedure of investigation of the initial stages of delayed fracture of the metal of HAZ of high-strength low-alloyed steels was developed, based on the measurement of notch opening displacement in long loading of hydrogenated samples ofrectangular section, subjected to thermal-cycling by passing current. The data on the notch opening displacement make it possible to estimate the level of intensity of plastic deformation and microcracks propagation in long loading of samples, simulating"AZ of high-strength low-alloyed steels. Given technique makes it possible to obtain the accurate and authentic data about the process, preceding the delayed fracture of the metal of HAZ of high-strength low-alloyed steels and to estimate it qualitatively.