Method for preparing large magnesium alloy ring piece through combination of centrifugal casting and ring forging

The invention discloses a method for preparing a large magnesium alloy ring piece by compounding centrifugal casting and ring forging, and belongs to the technical field of magnesium alloy material forming. The method comprises the following steps: firstly, preparing a large magnesium alloy ring piece through a centrifugal casting process, homogenizing the ring piece, determining ring forging process parameters, and carrying out ring forging on the ring piece; the technical key point mainly comprises the steps of determining the centrifugal rotating speed to prepare the magnesium alloy ring piece and selecting proper ring forging temperature and single-pass rolling reduction. When the outer diameter R < outer >/R < inner > of the circular ring is smaller than or equal to 1.15, the rotating speed is calculated according to a Constantinunov formula; and when the outer diameter R < outer >/R < inner > of the circular ring is greater than or equal to 1.15, calculating the rotating speed by using a gravity coeffic