Influence of trace elements and heat treatment on carbide morphology and properties of CD-2 steel

The purpose of the current investigation was to develop a modified ledeburite cast die steel with granular carbide, which, different from the conventional ledeburite cast die steel CD-2 with network carbide, had higher strength and toughness. By adding trace elements, grain and eutectic in the steel were refined, with a concomitant increase in divorced eutectic and decrease in segregation of Cr and Mo. After heat treatment between 1100 and 1130°C, network carbide changed into a granular form. As a result, the modified CD-2 steel with granular carbide gave higher impact toughness, fracture toughness and resistance to fatigue crack propagation compared to conventional CD-2 steel.