The current researches of the wear and spalling behaviors of wheel/rail materials focus on the field investigation rather than the mechanism.However,it is necessary and significant for clarifying the mechanism and relationship between the wear and spalling damage of railway wheel to test and reproduce the wheel damages in laboratory.The objective of this paper is to investigate the wear and spalling damage behaviors of railway wheel using a JD-1 wheel/rail simulation facility,which consists of a small wheel serving as rolling stock wheel,and a larger wheel serving as rail.The damage process of wheel roller is explored in terms of the creep ratio,axle load,and carbon content by means of various microscopic examinations.The experimental results show that the wear volume growth of wheel roller is proved to be proportional to the increase of the creep ratio and normal load between simulating wheel and rail.The increase of carbon content of wheel material causes a linear reduction in the wear volume.The microscopic examinations indicate that the rolling wear mechanism transfers from abrasive wear to adhesive and fatigue wear with an increase of tangential friction force,which results in the initiation of fatigue crack,and then aggravates spalling damage on the wheel roller surface.The surface hardness of material depends strongly upon its carbon content.The decrease of the carbon content of wheel material may alleviate spalling damage,but can cause a significant growth in the wear volume of wheel roller.Therefore,there is a competitive relationship between the wear and spalling damage of wheel material.This research proposes an important measure for alleviating or preventing the wear and spalling damage of railway wheel material.
利用CO2多模激光器在车轮试样表面获得Co基合金熔覆层，通过 MMS-2 A 微机控制摩擦磨损试验机对比研究了不同轴重下轮轨试样的磨损性能与损伤机理.结果表明，车轮试样激光熔覆处理后熔覆层组织明显细化，表面硬度明显提高，约为基体的1．5倍.轮轨试样摩擦系数与磨损率随轴重增加而增大，车轮磨损率仅为钢轨的1/5~1/8；随时间增加，轮轨试样磨损量呈线性增长趋势；随轴重增加，轮轨试样表面损伤越严重，相同条件下，车轮试样损伤比钢轨轻微，轴重较小时，车轮熔覆层磨损主要为粘着磨损和氧化磨损，钢轨主要为疲劳磨损与氧化磨损.随轴重增加，轮轨试样主要为严重疲劳损伤，氧化磨损较为轻微.
