车轴钢弯曲微动疲劳失效机理和寿命预测方法的研究

Bending fretting fatigue is the main failure mode of the high-speed train axle components. In this project, the failure mechanism and life prediction method of bending fretting fatigue for axle steel will be studied by combining with experimental study, finite element simulation and theoretical analysis. The non-proportional multiaxial ratcheting experiment will be carried out, and the multiaxial ratcheting evolution characteristics will be revealed, and then the cyclic ratcheting constitutive model under the framework of finite deformation which is used for subsequent finite element analysis of bending fretting fatigue process will be established; the influence of third body, surface roughness, cyclic bending load, normal force and friction coefficient on the bending fretting fatigue will be researched by combining experimental and numerical analysis. The damage evolution characteristics and failure mechanisms of bending fretting fatigue will be revealed, and then a new life prediction method of bending fretting fatigue and effective measures for preventing bending fretting fatigue will be proposed. The research achievements will enhance the knowledge level of the solid mechanics on the aspects of bending fretting fatigue damage and it will also give important theoretical supports for safety assessment and life prediction of high-speed train.

弯曲微动疲劳是高速列车车轴断裂的主要失效形式之一。本项目拟通过试验研究、有限元模拟和理论分析相结合的研究方法开展车轴钢的弯曲微动疲劳失效机理及其寿命预测方法的研究。通过系统的非比例多轴棘轮试验，揭示棘轮演化特性，以此建立有限变形框架下的循环棘轮本构模型，为后续弯曲微动过程的有限元分析提供理论模型；通过系统的弯曲微动疲劳试验研究和有限元模拟，分析第三体磨屑、表面粗糙度、循环弯曲载荷、法向载荷和摩擦系数等因素对弯曲微动疲劳的影响，揭示弯曲微动疲劳过程的损伤演化规律和失效机理，从而提出能合理预测弯曲微动疲劳寿命的方法和防护弯曲微动疲劳的有效措施。研究成果将提高固体力学在弯曲微动疲劳损伤领域的认识水平，同时为高速铁路的安全评估和寿命预测提供理论支持。

弯曲微动疲劳是高速列车车轴断裂的主要失效形式之一，会导致车轴的疲劳强度和寿命大大降低。本项目拟开展车轴钢的弯曲微动疲劳失效机理及其寿命预测的研究。通过单轴循环变形试验，揭示单轴棘轮演化特性，在有限变形框架下建立能合理描述循环棘轮行为的本构模型，为后续弯曲微动过程的有限元分析提供理论模型；通过系统的弯曲微动疲劳试验和有限元分析，讨论了循环弯曲载荷、法向载荷和摩擦系数等因素对弯曲微动疲劳过程的影响，揭示弯曲微动疲劳过程的损伤演化规律和失效机理，提出能合理预测弯曲微动疲劳寿命的方法。研究成果将提高固体力学在弯曲微动疲劳损伤领域的认识水平，同时为高速铁路的结构设计、安全评估和寿命预测提供理论支持。