SUPER-HIGH-STRENGTH TOOL STEEL HAVING HIGH IMPACT TOUGHNESS AND METHOD OF MANUFACTURING THE SAME

摘要

Disclosed is super-high-strength tool steel having high impact toughness, including 0.7 to 0.9 wt % of C, 0.4 to 0.6 wt % of Si, 0.4 to 0.6 wt % of Mn, 7.0 to 9.0 wt % of Cr, 1.5 to 2.5 wt % of Mo, 1.0 wt % or less (excluding 0 wt %) of V, and at least one of 0.1 wt % or less (excluding 0 wt %) of Ti and 0.1 wt % or less (excluding 0 wt %) of Ce, with the remainder of Fe and inevitable impurities. The super-high-strength tool steel having high impact toughness includes at least one of Ti and Ce, thus reducing primary carbide content in an as-cast state and exhibiting improved impact toughness at a high hardness level after solution treatment and tempering. In addition, a method of manufacturing super-high-strength tool steel having improved impact toughness at a high hardness level is provided.