Fractographic Analysis of the Destroyed Side Frame of the Truck of a Wreight Wagon

EN: The initial inspection of damaged frame in fracture revealed two sections with characteristic structural features. The area with traces of slight corrosion, representing a smooth surface, corresponds to the gradual movement of fatigue crack. The rest of fracture surface with signs of a dynamic destroy has a qualitatively different structure. The fatigue part occupies approximately 30% of the total cross-sectional area. The propagation front of fatigue crack, after reaching the outer and inner surfaces of vertical wall from the side of wheel, reaches half the length lower horizontal wall. The focus of origin fatigue crack, located in lower inner corner, when moving from vertical wall to horizontal part of the side frame, is difficult obtain access when visually inspecting the frame trolley.