Effect of carbon content on selection of slip system during uniaxial tensile deformation of lath martensite

The deformation behavior of lath martensite in medium-carbon steel was investigated using a scanning electron microscope and electron backscattering diffraction techniques and compared with that of low-carbon steel. There was a significant difference in the occurrence behavior of slip bands between the two grades of steel. In particular, the slip band occurrence is concentrated on specific type in the case of medium-carbon steel. About the origin of this particular phenomenon, it is indicated that the difference in the formation behavior of slip band results from the difference in microstructures due to different carbon content. The noticeable difference in the microstructure was the block width, which affected the selection of the slip system. The block boundary constraint obtained from the block width could be the key factor in the selection of a slip system for martensite that has a relatively higher-carbon content.