Production process of large-specification S31254 super austenitic stainless steel bar

The invention relates to the technical field of metal forging, in particular to a production process of a large-size S31254 super austenitic stainless steel bar, which comprises the following steps: casting S31254 super austenitic stainless steel by adopting an electric furnace + AOD + LF smelting process to obtain an electrode blank with the oxygen content of less than or equal to 20ppm; the electrode blank is subjected to electroslag remelting, and an electroslag ingot with the oxygen content smaller than or equal to 20 ppm is obtained; and the electroslag ingot is heated to 1200-1250 DEG C, heat preservation is conducted for 50-60 h, homogenization diffusion is conducted, then the electroslag ingot is cooled to 1140-1180 DEG C, heat preservation is conducted for 6-12 h, and the S31254 super austenitic stainless steel bar is obtained through discharging and forging. According to the method, the large-size precipitated-phase-free S31254 superaustenitic stainless steel bar is obtained through the production t