The researches and tests recently performed abroad on cyclic deformation behaviors, crack initiation, crack propagation and crackretardation properties of rail steels are introduced briefly.
简要地介绍了国外近年来有关钢轨钢的交变形变，疲劳裂纹的萌生，扩展、阻滞等方面的研究试验。
2
By observing the initial Angle of crack arid its propagating path, a simple model to predict the retardation effect of Z-shaped fatigue crack was proposed.
通过观察裂纹的开裂角及扩展路径，提出了一个能用来估算Z型裂纹过载迟滞效应的简单模型。
3
The theoretical analysis indicated that the crack closure effect was mainly responsible for the change of crack growth retardation in corrosion fatigue.