Abstract:In order to study the fatigue performance of Q460ME steel plate for rail vehicle body, MTS landmark electro-hydraulic servo fatigue testing machine was used to carry out fatigue tests on Q460ME steel plates with two types of thickness specifications. The stress ratio was -0.1 and the loading frequency was 60 Hz. The tests were carried out based on lifting method. The conditional fatigue limit parameters under different survival rates were calculated by means of stress concentration factor correction. The test results were compared with DVS1612 standard. It can be shown that the stress concentration factor of the test sample is 1.25, the lifting diagrams of Q460ME steel plate with two types of thickness specifications can be closed, and the fatigue limit values calculated by the lifting diagram decrease with the increase of thickness, in which the fatigue strength values of Q460ME with 5 mm and 8 mm thickness are significantly higher than that of S355 steel in DVS1612 standard. Obvious crack source, crack propagation zone and instantaneous fracture zone can be seen in the fracture section of three thickness specimens of Q460ME steel plate. The fatigue crack source occurs at the corner of the rectangular section surface and is a single crack source. There are obvious "beach" fatigue striations in the crack propagation zone, which are fan-shaped and perpendicular to the local crack propagation direction. The instantaneous fracture zone is ductile fracture, which reflects the good toughness of the sample