Research On Rolling Contact Fatigue Of Rail Steel

Rolling contact fatigue has being become a main problem of railway transportation with increasing the speed and the load. Investigateing of the formation mechanism of rail rolling contact fatigue would help to bring enormous economic benefit and decrease breakage of rail.Rail rolling contact fatigue of rail steel have been studied by using JD-1 rail-wheel tnbology simulating machine, based on abundant literature research of rolling contact fatigue and an application project of railway. The effects of load, rolling speed, wheel/rail attack angle and material on rolling contact fatigue have been focused on particularly. Main conclusions are drawn as follows:1. Hardness plays an important role in wear-resistance of material. High hardness leads to low wear volume. The wear-resistance depends on the heat treatment technics of rail steel;there is a competitive relationship between wear and fatigue, good wear-resistance does not always lead to good fatigue resistance. Wear volume with same test parameter lies on material hardness and treatment technique.2. Rolling friction coefficient depends obviously upon the rolling speed of rollers. High rolling speed leads to low rolling friction coefficient, the wear volume decreasing accordantly with the increasing of rolling speed under same experimental parameter.3. Vertical load is an important influencing factor on the rail rolling contact fatigue formation and development. Wear volume under high load is bigger than one under low load. The wear volume without braking force is smaller than one with braking force.4. The wear volume with little curve radius is bigger than one with big curve radius in simulating experiment.