High-strength and high-toughness bulletproof steel as well as preparation method and application thereof

The invention provides tempered-state high-strength high-toughness bulletproof steel. The tempered-state high-strength high-toughness bulletproof steel comprises the following chemical components in percentage by mass: 0.08 to 0.12 percent of carbon, 0.15 to 0.25 percent of silicon, 1.7 to 1.9 percent of manganese, less than or equal to 0.015 percent of phosphorus, less than or equal to 0.003 percent of sulfur, 0.025 to 0.060 percent of acid-soluble aluminum, 0.050 to 0.060 percent of niobium, 0.135 to 0.170 percent of titanium, 0.22 to 0.32 percent of molybdenum, 0.23 to 0.30 percent of chromium and less than or equal to 0.0045 percent of nitrogen. The bulletproof steel machining method overcomes the defects of high cutting and welding difficulty in the bulletproof steel machining process, and is remarkable in effect and worthy of popularization. 本发明提供了一种回火态高强度高韧性防弹钢，其化学组成与质量分数包括：碳0.08-0.12％，硅0.15-0.25％，锰1.7-1.9％，磷≤0.015％，硫≤0.003％，酸溶铝0.025-0.060％，铌0.050-0.060％，钛0.135-0.170％，钼0.22-0.32％，铬0.23-0.30％，氮≤0.0045％。