EFFICIENCY OF DIFFERENT METHODS OF STRENGTHENING TREATMENT OF WELDED JOINTS

摘要

The efficiency of selection of non-damaging modes of vibration treatment of welded elements of low-carbon steel metal structures with the purpose of reducing residual stresses in them without danger of fatigue fracture at the stage of technological treatment is shown. The comparative fatigue investigations showed an increase in the service life of vibrotreated welded joints and an increase in their fatigue limit at the increase of test base. A method for determination of fatigue limits for butt welded joints of low-carbon steel after different modes of high-frequency mechanical peen- ing. using experimental data of groove depth measurement, was proposed. The efficiency of increasing their fatigue limit is shown depending on the speed of high-frequency mechanical peening and the amplitude of oscillations of the working tool. The results of experimental investigations of increasing fatigue resistance of welded joints of low-alloy and low-carbon steels under harmonic and repeated impact loading at the temperature of -60 °C after high-frequency mechanical peening, argon-arc, explosive, and mechanical treatments were analyzed and a comparative analysis of their efficiency was presented. 23 Ref., 4 Tables, 10 Figures.