High-homogeneity titanium alloy cast ingot and preparation method thereof

The invention belongs to the technical field of titanium alloy processing, and discloses a high-homogeneity titanium alloy cast ingot and a preparation method thereof. The preparation method comprises the following steps: mixing and pressing sponge titanium and intermediate alloy raw materials into a plurality of electrode blocks, and welding the plurality of electrode blocks to obtain a consumable electrode; the consumable electrode and the auxiliary electrode are welded to obtain a welding electrode; a welding electrode is smelted for the first time, the ratio of the diameter of a crucible to the smelting speed is 40-50, the arc stabilizing current is 5-10 A, and the period is 240-300 s; the ratio of the diameter of the crucible to the smelting speed is 35-45, the arc stabilizing current is 10-15 A, and the period is 120-240 s; and during third smelting, the ratio of the diameter of the crucible to the smelting speed is 30-40, the feeding rate V2 meets the condition that V2 is larger than or equal to-(t/75)