Patent attributes
An iron-based alloy comprises 1.5 to 2.5 wt % of C, 0.25 to 4.75 wt % of Ni, and W and V in quantities surrounded by the line L as shown in FIG. 1 of the attached drawings with a balance of Fe and inevitable impurities. The iron-based alloy is obtained by a first heat treatment for applying a solid solution treatment by rapidly cooling the iron-based alloy from a temperature of an austenite forming temperature or more to consequently obtain a mixed matrix comprising a base matrix of martensite and remaining austenite phases and a non-molten carbide, and a second heat treatment for cooling the iron-based alloy after precipitating an MC type carbide within an eutectoid transformation temperature range to consequently precipitate a low carbon content austenite phase.