The work discussed the impact of micro-defects on the resistance of welds against fatigue. With the rotating bending numerous samples of steel, with micro-defects in the various states, prepared by using simulation of thermal cycles of welding and by heat treatment in a furnace were tested. It has been experimentally studied the growth rate of small and large cracks. In work it is proved that the formation of cracks in the man-made micro-defects, whose size is comparable with the largest microstructural units of steel, a function of local residual stresses.
COBISS.SI-ID: 240161536
This work deals with the characterization of heat-cutted edge of the elements of high-strength steel S960Q. The results of high cycle fatigue on resonant pulsator at constant amplitude load and load ratio of 0.1 are given. Represented is the numerical model for simulation of the initiation of cracks, which is based on Tanaka-Mura model. The model is taken into account the surface roughness and the size of the heat affected zone, depending on the cutting parameters. Microstructural changes that occur by cutting are covered by simulating synthetic microstructure
COBISS.SI-ID: 12567318