Fatigue Behaviour of Medium Carbon Steel of Different Grain Structures

This paper investigated the effect of heat treatment operations on the fatigue resistance of low carbon steel. Specimens after preparation for fatigue testing were subjected to annealing, normalizing and quenching heat treatment. Results show that the annealed specimen had the largest number of cycles to failure, indicating a high fatigue resistance. The microstructure of the specimens was examined in other to corroborate the obtained property with the microstructure. When compared with the untreated specimen, the annealed specimen (with optimum fatigue resistance) shows a large grains size of pearlite which was distributed across the entire surface of the microstructure. Generally, it was found that the size and distribution of specimens’ grains affect the resistance of the low carbon steel to fatigue failure. Keywords: fatigue, low carbon steel, heat treatment, microstructur