【作者】 庞建超； 李守新； 张哲峰；

【Author】 J.C.Pang;S.X.Li;Z.F.Zhang;Shenyang National Laboratory for Materials Science, Institute of Metal Research,Chinese Academy of Sciences;

【机构】 中国科学院金属研究所沈阳材料科学国家(联合)实验室；

【摘要】 本文通过Basquin公式系统研究了不同钢铁材料的S-N曲线。为了便于比较,首先对S-N曲线进行定义,随后总结分析了S-N曲线参数(疲劳强度指数和疲劳强度系数)随抗拉强度的变化。对于相同类型S-N的钢铁材料,其疲劳强度系数都随抗拉强度的提高而线性提高,而疲劳强度指数随抗拉强度的增加先基本不变然后线性下降。控制这种现象的疲劳机制可以简单解释为:疲劳强度系数的变化由强化机制决定;疲劳强度指数变化受微观组织结构和裂纹萌生位置的影响。在设计或制备钢铁材料时可以通过适当调整疲劳强度系数和疲劳强度指数来提高其疲劳强度。更多还原

【Abstract】 S-N curves of different steels were determined according to certain qualifications systematically for comparison and investigated by Basquin relation. The change of parameters(fatigue strength coefficients and exponents) of these S-N curves with increasing tensile strength was analyzed and summarized. For the steels with the same type of S-N curves, as tensile strength increases, their fatigue strength coefficients linearly increase and fatigue strength exponents almost keep unchanging at first and then decrease linearly. In addition, the fatigue mechanisms controlling the parameters of S-N curves with tensile strength increasing were discussed. It is briefly explained that the fatigue strength coefficient can be improved by strengthening mechanisms, and the change of fatigue strength exponent with tensile strength may be influencedby the changes of fatigue crack initiation sites and the microstructures of steels treated by different heat treatments. Through properly adjusting fatigue strength coefficients and fatigue strength exponents the fatigue strength can be improved in the course of the selection and preparation of steels.更多还原