Near net shape forming process of a titanium alloy impeller

The complex components such as the impellers are difficult to manufacture because of their complicated shapes and high requirements of mechanical properties. In order to form the titanium impeller precisely two forming schemes with two die devices were designed. Three-dimensional finite element method (FEM) was used to simulate the forming process of the impeller and study the metal flow laws. Several key factors such as the loading scheme, die structure and billet shape were studied in detail. The simulated and experimental results show that the titanium alloy impeller with radial twisted blades can be precisely forged with the isothermal enclosed die forging technology. The local loading technology can control metal flow, so the forgeability of the impeller blades can be improved and the flaws such as underfill and flash can be avoided.