Preparation process of low-temperature-impact-resistant super duplex stainless steel

The invention discloses a low-temperature-impact-resistant super duplex stainless steel preparation process which comprises the following steps: a, melting raw materials into crude molten steel to obtain a product A; b, blowing the product A to an oxidation end point, and sequentially carrying out pre-reduction and reduction to obtain a product B; c, the product B enters an LF furnace, deoxidation alloy powder and a feeding line are adopted for slag surface deoxidation and precipitation deoxidation, white slag operation is ensured, and a product C is obtained; d, the product C is poured into a continuous casting billet or a mold cast ingot, and a product D is obtained; e, the product D is conveyed to a steel rolling mill or a forging mill in a red conveying mode, rolling or forging cogging is conducted after heating is conducted in a heating furnace, and an intermediate product is obtained; f, for an intermediate product obtained through rolling, water cooling is conducted immediately after cogging, surface f