服役损伤对制动盘疲劳裂纹扩展行为的影响  

Effect of service damage on fatigue crack growth behavior of brake disc

作　　者：李志强[1] 韩辰 张晓康 杨智勇[1] LI Zhiqiang;HAN Chen;ZHANG Xiaokang;YANG Zhiyong(School of Mechanical,Electronic and Control Engineering,Beijing Jiaotong University,Beijing 100044,China)

机构地区：[1]北京交通大学机械与电子控制工程学院,北京100044

出　　处：《铁道科学与工程学报》2024年第10期4253-4265,共13页Journal of Railway Science and Engineering

基　　金：中央高校基本科研业务费专项资金资助项目(2021JBM023);国家自然科学基金资助项目(52002018)。

摘　　要：制动盘是高速列车制动系统的重要元件,其复杂的服役工况会使制动盘出现多种形式的服役损伤,影响制动盘后续的可维修性和服役安全性。选取未服役制动盘和产生翘曲变形且摩擦面出现疲劳裂纹的服役后制动盘为研究对象,通过测试服役前后制动盘材料在不同温度下的拉伸力学性能,构建了受摩擦面深度和温度双参数影响的力学性能衰退模型来表征制动盘的材料损伤。通过构建不同制动工况下制动盘三维瞬态仿真模型,得到了服役后制动盘的结构变形和残余应力状态来表征制动盘的结构损伤。基于Paris理论进行制动盘疲劳裂纹扩展寿命分析,评估了服役损伤对制动盘疲劳裂纹扩展能力的影响。结果表明:长期服役后制动盘本体材料力学性能会发生衰退,从摩擦面表层至心部呈现梯度分布,近表层材料强度下降约20%,制动盘残余应力释放后会使盘体产生碟形翘曲变形。服役后制动盘的力学性能衰退使裂纹前缘的应力强度因子水平显著高于服役前制动盘,摩擦面中部裂纹沿制动盘径向的扩展速率大于沿深度方向,使裂纹深长比不断减小。与服役前制动盘相比,服役后制动盘摩擦面中部裂纹从0.5 mm扩展至70 mm的扩展寿命降低了48%。螺栓孔处疲劳裂纹扩展初期主要沿深度方向扩展,随着裂纹尺寸增加沿制动盘径向与深度扩展速率逐渐一致,服役后制动盘螺栓孔裂纹从0.5 mm扩展至50 mm的扩展寿命与服役前相比降低了29%。本文的研究方法可用于不同损伤程度的制动盘本体性能表征与失效分析,对服役后制动盘的检修维护、保障制动盘的安全运用具有工程参考价值。The brake disc is an important component of high-speed train braking system.Its complex service conditions cause various forms of service damage to brake disc,which affects its subsequent maintainability and service safety.The brake disc before service and the serviced brake disc with warping deformation and fatigue cracks on the friction surface were selected as the research objects.By testing the tensile mechanical properties of the brake disc material before and after service at different temperatures,a mechanical performance degradation model affected by the depth and temperature on the friction surface was constructed to characterize the damage of the brake disc material.By constructing the three-dimensional transient simulation model of the brake disc under different braking conditions,the structural deformation and residual stress state of the brake disc after service were obtained to represent the structural damage of the brake disc.The fatigue crack growth life of brake disc was analyzed based on the Paris theory,and the influence of service damage on the fatigue crack growth ability of brake disc was evaluated.The results show that the mechanical properties of the brake disc material decline after long-term service.The mechanical properties show a gradient distribution from the surface to the center of the friction surface.The strength of the near-surface material decreases by about 20%.A dish-warping deformation of the disc occurs after the release of the residual stress in the brake disc.Under the effect of the degradation of the mechanical properties of the brake disc after service,the value of stress intensity factor of the crack is significantly higher than that of the brake disc before service.For the crack in the middle of friction surface,the crack growth rate in radial direction is higher than that in the depth direction of brake disc,which makes the depth-to-length ratio of crack shape decrease continuously.Compared with the brake disc before service,the crack growth life for the crack in the

关 键 词：制动盘 服役损伤 裂纹扩展 性能衰退 残余应力 

分 类 号：U270.35[机械工程—车辆工程]