Abstract
In this paper, the results of a recent study aimed at understanding the bending fatigue response of two carbon steels is presented and discussed. The two carbon steels chosen are the ones preferred and used for a spectrum of industrial applications. Bend test specimens of the two carbon steels were prepared and conformed to specifications used in several earlier studies. The machined test specimens were deformed in bending fatigue over a range of maximum load, at a positive load ratio of 0.1, and the number of cycles to failure was recorded. The specific influence of chemical composition on bending fatigue life of the carbon steels is presented. The fracture surfaces of the deformed and failed specimens were examined in a scanning electron microscope to establish the macroscopic mode of fracture and to concurrently characterize the intrinsic features and establish the microscopic mechanisms governing fracture. The influence of nature of loading and maximum load on bending fatigue life is discussed in light of chemical composition and intrinsic microstructural features of the chosen carbon steel.