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将Ｗｉｌｌｅｎｂｏｒｇ的超载残余应力场模型与裂尖形变动力学、裂尖表面析氢反应电化学动力学以及裂尖材料内部氢的扩散动力学和热力学相结合，建立了氢脆腐蚀疲劳裂纹扩展（ＣＦＣＧ）超载效应的定量描述模型，给出了超载对裂尖表面析氢电化学反应及裂尖氢扩展影响的一系列判据和表达式．用上述模型进行的预测表明，对于超高强度钢，当两次超载周次之间裂纹扩展长度ａｄ远小于超载塑性区尺寸ｒｐＯＬ与恒载塑性区尺寸ｒｐＣＬＡ之差，即ａｄ＜＜ｒｐＯＬ－ｒｐＣＬＡ时，ＣＦＣＧ会发生比空气疲劳还强烈的超载迟滞效应．而当ａｄ＞ｒｐＯＬ－ｒｐＣＬＡ时，可能会发生超载加速效应．这种预测在后文中由试验的宏观规律与断口特征得到充分验证．
In this paper, Willenborg’s model of overloading residual stress field is combined with the crack tip deformation kinetics, the electrochemistry kinetics of hydrogen evolution reaction at the crack tip surface, and the diffusion kinetics and thermodynamics of the hydrogen inside the crack tip material to establish the hydrogen embrittlement corrosion fatigue crack growth (CFCG) The quantitative description model of the overloading effect is given, and a series of criteria and expressions for the influence of overloading on the hydrogen evolution reaction and the hydrogen evolution at the crack tip are given. Prediction using the above model shows that for the ultra-high strength steel, when the crack propagation length ad between two overloaded cycles is much smaller than the difference between the rpOL of the overloaded plastic zone and the rpCLA of the dead zone, ad << rpOL-rpCLA , CFCG will experience a more severe hysteresis of overloading than air fatigue. When ad> rpOL-rpCLA, an overloading acceleration effect may occur. This prediction is fully verified by the macroscopic rules and fracture characteristics of the test in the following text.