Abstract：After heat treatment of 25MnB track shoe, the sample with unqualified elongation was comprehensively analyzed. The chemical composition was detected using direct reading spectrometer. The gas composition including N, H and O was detected using oxygen-nitrogen-hydrogen analyzer. The metallographic structure and non-metallic inclusion levels were inspected using metallographic microscope. The fracture analysis of sample was conducted using scanning electron microscopy(SEM). It was found that the cooling rate of track shoe was slow in the core of grouser, leading to the formation of nonuniform structure. Moreover, the presence of ferrite led to the unqualified elongation. By changing the cooling water nozzle to increase the cooling water flow rate, the cooling rate of track shoe quenching was accelerated. Thereby the generated tempered martensite with uniform structure was formed, and the elongation of track shoe could meet the requirements of the enterprise standard.
2022, Vol. 40 
