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一、关于金属疲劳的概念及其特征长时间受交变载荷作用的轴会在远低于轴(材料)的强度极限的应力下,突然破坏,而没有显著的残余形变,这种现象称为轴的疲劳破坏。曾经有人从无数次的实验确定:当交变应力大于某一定数值时,则在应力交变的次数达到某一数目之后,在轴中就有裂纹出现,这种裂纹叫做疲劳裂纹。这种裂纹通常发生在轴表面上最大应力的地方及轴有缺陷的那些位置。裂纹在开始形成时很小,并非肉眼所能看见,
First, the concept of metal fatigue and its characteristics A long time by the role of alternating load axis will be much lower than the shaft (material) under the stress of strength, and suddenly destroyed without significant residual deformation, this phenomenon is called Axis fatigue damage. There have been numerous experiments to determine: When the alternating stress is greater than a certain value, then the number of stress changes in a certain number of times, there are cracks in the shaft, the crack is called fatigue. This type of crack usually occurs where the maximum stress is on the shaft surface and where the shaft is defective. Crack at the beginning of the formation is very small, not visible to the naked eye,