In this study, attempts were made to harden the surface of ferritic flake graphite cast iron, which is rarely used due to its poor strength, by friction stir processed (FSP). As a result, it was clarified that Vickers hardness of above 700HV can be obtained even for ferritic matrix due to the formation of fine martensite similar to other cast irons. Additionally, the effects of the graphite shape and microstructure of the matrix on FSP conditions were investigated.
