Some microstructural aspects of melt-spun D2 steel

Commercial D2 steel has been rapidly solidified using melt spinning technique. Effect of substrate velocity (V-s) on ribbon thickness (t) has been examined and found to follow the empirical relationship (t) over bar = K V-s(-b). Microstructure of melt-spun ribbons was examined along the length and width across the thickness of the ribbon. The morphological features have been observed to vary from cellular to dendritic depending upon the cooling rate which in turn varies from melt-wheel contact surface to air side surface of the ribbons. TEM study of the as-spun ribbon sample revealed M7C3 type carbide in the interdendritic region of metastable austenite