Research of the Overloading Influence on the Propagation of Semi-Elliptical Surface Cracks with Different Shape Configurations in Low-Alloy Steel

The influence of a single tensile overload on the surface semi-elliptical cracks growth retardation of in semi-natural samples of low-alloy steel 09Mn2Si was considered. Experimental studies of tensile overloads influence on the surface cracks growth retardation were carried out, and the simulation of the surface cracks growth retardation was carried out using the specialized program AFGROW. A good convergence of the results obtained by the two methods was established. The delay in the surface cracks growth with different coefficients of their shape ratio was studied depending on the level of overloads, the range of the stress intensity factors of the main cycle, and stress ratio of the cycle. The regularities of the surface cracks growth under the influence of tensile overload have been established, depending on the specified factors.