Welding method of titanium alloy multilayer plate and titanium alloy multilayer plate

The invention discloses a welding method of a titanium alloy multilayer plate. The welding method comprises the following steps: 1) to-be-welded titanium alloy plates are stacked in sequence, brazingsolders are arranged on the surface to-be-welded plates, and meanwhile metal foils are arranged between the alloy plates for laser splicing on the titanium alloy multiplayer plate to replace the brazing solders; and 2) pressure is applied to the stacked plates, the plates are heated in a vacuum environment and are subjected to heat preservation for a preset time, the brazing and the diffusion welding are synchronously completed, and the heating temperature does not exceed the phase change point of part materials. The metal foils for diffusion welding are free of melting, and other elements arecompletely not introduced or only a small number of other elements are introduced when element diffusion occurs between the metal foils and a substrate, so that the crystal grain growth and the tissue phase change of the subs