This work verified the microstructural and mechanical properties evolution of three different carbon steels 0.1%C, 0.22%C and 0.54%C subjected to thermal cycling. 2, 4, and 6 thermal cycles were investigated and for each thermal cycle, the specimens were austenitized at 900ºC and inter-critically treated at 740ºC with intermediate water quenching. The initial and final mitrostructures of all specimens were analyzed by quantitative metallography using optical microscopy. The effect of cycling on the tensile properties of the steel samples were evaluated by testing standard samples to failure on Monsanto Type-N tensometer and the hardness values were measured on Rockwell B hardness scale. The microstructure revealed a mixture of ferrite, martensite and traces of bainite after the second cycle, which were rather more uniformly distributed after the fourth cycle. The specimen after the whole processing cycles achieved a Brinell hardness value varying from 15%-29%.
