The invention discloses a liquid die 
forging and rolling compound formation method for an aluminum 
alloy irregular-section large ring piece. The method comprises the following steps of: 
smelting, performing liquid die 
forging, homogenizing, performing afterheat isothermal rolling, performing 
thermal treatment and finishing, wherein the step of performing liquid die 
forging comprises the following substeps of: fixing a liquid die forging mold on an indirect 
extrusion casting machine, pouring a quantitative amount of aluminum 
alloy solution obtained through 
smelting into the liquid die forging mold at the pouring temperature of between 650 and 730 DEG C, pressurizing at the speed of 35 to 40 mm / s, filling for 1 to 6 seconds at the specific pressure of 100 to 200 MPa, keeping the pressure for 35 to 60 seconds, and thus obtaining a similarly final section ring blank; and the step of performing afterheat isothermal rolling comprises the following substeps of: cooling the homogenized similarly final section ring blank to the temperature of between 430 and 480 DEG C, and performing afterheat isothermal rolling on a radial shaft compound ring rolling 
machine. According to the liquid die forging and rolling compound formation method for the stainless steel irregular-section large ring piece, the flow of a blank preparation process for an aluminum 
alloy ring piece can be simplified, the cost can be reduced, and the production efficiency can be improved; and furthermore, the 
microstructure state of the aluminum alloy ring piece can be effectively improved, and the comprehensive mechanical performance is improved.