Alloy steel and preparation method and application thereof

The invention provides alloy steel and a preparation method and application thereof. The alloy steel comprises the following components of, in percentage by mass, 0.24-0.29% of carbon, 0.20-0.35% of silicon, 1.15-1.35% of manganese, 0-0.012% of phosphorus, 0-0.010% of sulfur, 1.35-1.45% of chromium, 0.04-0.08% of niobium, 0.10-0.18% of molybdenum, and the balance Fe and unavoidable impurities. Thepreparation method comprises the following steps: mixing the raw materials in the formula amount, smelting and casting, forging, rolling and performing heat treatment to obtain the alloy steel. According to the alloy steel provided by the invention, the content of the niobium and chromium elements is increased, the content of the molybdenum element is reduced, the cost of the alloy steel is low,and the alloy steel has the advantages of high strength and good toughness. 本发明提供了一种合金钢及其制备方法和用途。所述合金钢按组分质量分数包括：碳0.24-0.29％，硅0.20-0.35％，锰1.15-1.35％，磷0-0.012％，硫0-0.010％，铬1.35-1.45％，铌0.04-0.08％，钼0.10-0.18％，余量为铁和不可避免的杂质。所述制备方法包括：