Microstructural Characterization of Carbides in a Cast High-Speed Steel Using Different Metallographic Techniques

High-speed steels are mostly manufactured by casting and they exhibit a characteristic dendritic microstructure with primary carbides. In this study, the morphology of carbides in a cast high-speed steel is investigated using light and scanning electron microscopes. The morphology and structure of the carbides were revealed by means of different metallographic techniques such as chemical and electrolytic etching and color metallography. The combination of these metallographic techniques gives different approaches to how different primary carbide morphologies can be observed in the martensitic structure. Besides, microanalysis was carried out to determine the chemical composition of primary carbides using SEM/EDX.