The Influence of Wagon Structure Part Shape Optimization on Ultimate Fatigue Strength

This study investigates how shape optimisation affects the ultimate fatigue strength of a mechanical part. The mechanical part chosen for this type of investigation is an axle guard of running gear elements of the Hccrrs 2x2 axle car-carrying type. The static and fatigue strength analysis procedure, according to standard UIC 517, and numerical methods have been applied. Material properties were determined experimentally and the necessary numerical calculations were performed using the finite element method. Observed axle guard is exposed to low cycle fatigue. curves and material properties of steel quality S355J2+N are obtained by combining theoretical formulae and a mathematical function. According to obtained experimental and numerical results the number of cycles until failure for the both shapes of axle guards is obtained.