Cold work die steel and preparation method thereof

The invention discloses cold work die steel which is prepared from the following components: 2.0-2.25 percent of C, 11.5-12.5 percent of Cr, 4-4.5 percent of V, 0.25-0.5 percent of Si, 0.2-0.5 percent of Mn, 0.7-1.5 percent of Mo, 0.1-0.15 percent of Al, 0.15-0.2 percent of Re, less than or equal to 0.01 percent of S, less than or equal to 0.025 percent of P, less than or equal to 0.015 percent of N and the balance of Fe and inevitable impurities. The cold work die steel has the excellent performances such as high hardness, strength, wear resistance, toughness, high hardenability and hardening capacity. The preparation method comprises the following steps: melting in a neutral crucible, performing LF furnace external refining and VD vacuum degassing, adding Re to perform modification on molten steel, casting the molten steel into an electrode bar, performing electroslag remelting to smelt into steel ingots, and finally, heating, performing billet forging to produce the bar. The production process is simple in flow and low in cost and has excellent market values.