Experimental Investigation Into Fatigue Behaviuor of EN- 8 Steel (080M40/AISI 1040) Subjected to Heat Treatment and Shot Peening Processes

EN-8 steel (also known as 080M40 or AISI 1040 steel) has been widely used in the fields of power transmission shafts, gears and automobile crankshafts due to its unique metal properties and versatility. Parts of these products may fail during cyclic loading which may result in production losses and delays. The objective of the study is to investigate the fatigue behaviour of EN-8 steel concerning its mechanical properties, such as tensile strength, yield stress, elongation and hardness, when it is subjected to heat treatment and shot peening processes. The fatigue test was conducted on samples that were not treated by any process (without treatment - WT), samples subjected to quenching and tempering (Q&T), shot peened samples (SP), and samples subjected to a combination of quenching and tempering and the shot peening process (Q&T and SP). One way ANOVA was performed on the average number of cycles of different treatments to validate the fatigue strength