The invention discloses a preparation method of a
magnesium alloy plate with a gradient twin structure, and belongs to the technical field of heterostructure material preparation. According to the method, firstly, a
magnesium alloy plate serves as a base plate,
magnesium alloy wires of the same mark are adopted for double-heat-source
auxiliary heating stirring friction
solid-phase additive manufacturing, and a deposition plate with
crystal grains preferentially oriented in the thickness direction is obtained by regulating and controlling the
heating temperature and deposition head process parameters; keeping the heating state of the substrate, performing heat source-assisted ultrasonic rolling on the deposited plate, and enabling
crystal grains in the thickness direction of the plate to generate twinning deformation of different degrees by regulating and controlling rolling parameters; and finally, separating the substrate from the deposition plate to obtain the
magnesium alloy plate with the gradient twin structure. Heterogeneous particles are not introduced, the material is pure, the technological process is short, the production efficiency is high, the cost is low, the prepared plate is small in grain, the gradient twin
crystal structure penetrates through the thickness, the comprehensive performance is excellent, and the method is suitable for industrial production and can be applied to the fields of automobiles,
aerospace,
medical instruments and the like.