Flow Forming of Aircraft Engine Components

Aircraft engine components are often an assembly of several parts that are manufactured using various processes deep drawing, machining, among others. Sheet metal forming requires expensive tooling and is performed in numerous steps, increasing lead-time. Furthermore, with the ever-increasing costs of raw material, machining parts out of forged or cast rings is becoming less cost effective as up to 90 of the material can be wasted. For these reasons, the use of near net shape manufacturing methods is becoming inevitable. An alternative forming process is here investigated flow-forming, process well adapted to axisymmetric parts. The amount of forming steps, welding and machining could be significantly reduced, hence reducing lead-time and manufacturing costs. Metallurgical and mechanical properties of a flow-formed case will be presented and compared with material characteristics of cases manufactured by machining of forged rings. It will be shown that both forming processes yield to equivalent results.