Abstract: According to an embodiment, the described hot mold steel may be excellent in high thermal conductivity to decrease the temperature difference in materials at high temperature, thereby making heat-checking properties excellent. When the hot mold steel according to the present disclosure is used for die casting, the cooling rate of the product produced using the die casting is quick, thereby improving the physical properties of the produced product and shortening the cooling time to improve productivity. Furthermore, the hot mold steel may have excellent high temperature durability, such that the die casting produced using the hot mold steel may have characteristics of a long life cycle.

Abstract: Provided is a mold steel for plastic injection that is excellent in fatigue strength and tensile strength and available for long term use, where the mold steel includes: 0.15 to 0.40 wt. % of carbon (C), 0.15 to 0.50 wt. % of silicon (Si), 0.70 to 1.50 wt. % of manganese (Mn), 0.50 to 1.20 wt. % of nickel (Ni), 1.50 to 2.50 wt. % of chrome (Cr), 0.25 to 0.70 wt. % of molybdenum (Mo), 0.20 wt. % or less of vanadium (V), 0.010 wt. % or less of boron (B), and a trace of iron (Fe) and a plurality of impurities.