High-toughness stainless steel and ultra-purification smelting method thereof

The invention discloses an ultra-purification smelting method of high-toughness stainless steel. The component system of the high-toughness stainless steel comprises the following components in percentage by mass: 0.1 to 0.15 percent of C, 10 to 15 percent of Cr, 10 to 14 percent of Co, 4 to 8 percent of Mo, 1.5 to 3.0 percent of Ni, 0.5 to 1.0 percent of V, 0.01 to 0.05 percent of Nb and the balance of Fe and other inevitable impurities. The ultra-pure purification smelting method comprises the following steps: (1) finely selecting raw materials; (2) raw material treatment; (3) raw material purification; (4) vacuum induction melting; and (5) vacuum arc remelting. By means of the method, harmful elements and residual elements in the high-toughness stainless steel can be stably controlled to be extremely low in content, meanwhile, it is guaranteed that the steel is pure, and the problem of ultra-high purity of the high-toughness stainless steel is effectively solved. The invention further discloses the high-st