Isothermal precision forging of aluminum alloy ring seats with different preforms using FEM and experimental investigation

Abstract

7A09 aluminum alloy ring seat of airplane is subjected to isothermal precision forging. The influence of the different preforms on flow line, microstructures, mechanical properties, and defects of the forging is comprehensively investigated by means of experiments and FEM. Isothermal precision forging of the ring seat is implemented on the basis of three disk preforms with the height of 15, 25, and 35 mm, respectively. The experimental results indicate that the flow of metal along the radial direction increases with the increase in the height of the preform, and large plastic deformation of metal along the radial direction contributes to forming flow line of the forging. In the case of the preform with the height of 35 mm, the forging exhibits perfect profile, where there exist no defects such as underfilling and folding, while breaking of flow line frequently occurs. Furthermore, the high preform causes the forging to possess finer grain and substructure and consequently contributes to enhancing comprehensive mechanical properties. As a consequence, the preforging preform is appropriately designed so that high-quality forging with perfect flow line can be obtained by means of the optimum process procedure.