B 级车轮铸钢的疲劳可靠性设计 Goodman-Smith 图

为获得任意可靠性水平下铁道车辆B级车轮铸钢的疲劳设计依据，利用材料的概率机械性能、疲劳极限、中短与长寿命范围的疲劳S-N曲线参数，确定该铸钢的疲劳可靠性设计Goodman—Smith图．图中用车辆行驶里程度量车轮的疲劳寿命．采用Goodman修正考虑平均应力效应，疲劳强度由中短与长寿命范围的概率疲劳S-N曲线确定．图中八边形的顶点坐标由全概率模式求解．

Goodman-Smith Diagram for Fatigue Reliability Design of Grade B Cast Wheel Steel

To obtain fatigue design data under different reliabilities for grade B cast wheel steel for railway vehicles, a Goodman-Smith diagram of the steel was obtained using probabilistic mechanical properties, fatigue limits, and the data available in S-N curves of the steel covering mid-and-long fatigue lives. The fatigue lives were measured by the running distance of the wheel. The effects of average stresses on fatigue properties were considered in terms of Goodman modification, and the fatigue strength was evaluated with the probabilistic fatigue S-N curves covering the mid-and-short and long lives. The coordinates of octagon vertices of the diagram were determined on an entire probabilistic space.