| The railway transportation systems possessing a lot of unique advantages are irreplaceable in today's transportation. But with the progress made, some problems never seem to leave us, and moreover, new problems continue to crop-up. The wheel tread damage included in the issue as relationship between wheel and rail is particularly prominent, hinders the development of railway transportation systems greatly. Wheel failure can not only affect the normal operations, but also endanger the safety of rail transport. Therefore, the study on wheel tread damage mechanism is of positive significance for improving the economic efficiency of rail transport and the promotion of rail transport.The wheel tread damage is integration of wheel-rail interaction which is a complex process including tribological phenomena and the material response to external impact, so it is subject to a large number of factors. In order to provide some valuable conclusions to reduce the tread damage, rolling friction and wear behaviors of wheel steel under various conditions were investigated with NENE2 fretting fatigue-testing machine and reciprocating rolling testing apparatus in this thesis. Main conclusions were drawn as follows:(1) The characteristic of rolling wear is significantly different under different braking force, and changes regularly. The wear damage of wheel surface would transform from slight scratch to abrasive wear, adhesion and fatigue spalling with the coefficient of friction increasing.(2) With the frequency increasing, the wear mechanism of wheel steel subjected to partial slip makes a transform from abrasive wear to fatigue wear.(3) Normal force has a significant impact on wear. The real contact area is droved by normal force. Under braking conditions, large normal force can lead to spalling more easily.(4) The spalling of wheel steel begins with transverse surface cracking in reciprocating rolling test.(5) Coefficient of friction and wear are both decreased with the existence of water.
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