Corrosion-resistant casting and preparation process thereof

The invention discloses a corrosion-resistant casting and a preparation process thereof, and relates to the technical field of castings, the corrosion-resistant casting comprises a stainless steel casting base material and a corrosion-resistant coating, and the corrosion-resistant coating covers the surface of the stainless steel casting base material; the stainless steel casting base material comprises the following chemical components: less than or equal to 0.10% of C, 15%-20% of Cr, 0.3%-0.5% of Si, 15%-17% of Mn, 0.8%-1.5% of Mo, 1%-1.5% of Re, 0.2%-0.6% of Sn, less than or equal to 0.025% of P, less than or equal to 0.040% of S, 0.8%-1% of Al, 1.5%-1.8% of Ba and 4%-4.8% of Ni. According to the method, 15%-17% of Mn and 0.6% of Sn are added to replace Ni, a matrix structure is converted into an austenite-ferrite type, a certain amount of Re is used for strengthening modification treatment, the special stainless steel material suitable for being applied to the strong saline-alkaline environment is obtaine