抄録
Eutectoid steels are used for variable kinds of industrial components. In addition, these components are usually pre-strained before use during production process or machining one. The object of this study was to investigate the microscopic behavior of eutectoid steel during static tension, pre-strain process and to evaluate the effect of pre-strain on the fatigue strength of the steel. The main results obtained in this test are as follows: (1) There is no obvious yield point of eutectoid steel. (2) Under the pre-strain process (ε_p=7%), micro-cracks initiate in the surface of specimen. (3) All fatigue limits of different pre-strain ratio are lower than the original one. (4) There are no obvious fatigue limits variations for different small pre-strain ratio. (5) Fatigue cracks initiate from slip line, or micro-cracks that are generated in the process of plastic strain.
