New Hybrid Manufacturing Routes Combining Forging and Additive Manufacturing to Efficiently Produce High Performance Components from Ti-6Al-4V

Abstract High-performance components from titanium alloy Ti-6Al-4V are used in many industries, particularly in aerospace, but also in the automotive and medical market. Traditionally, such components are produced by hot forging and subsequent post processing. The multi-stage forging process requires several expensive dies and leads to components with a high material oversize. Therefore, costly machining operations with machining removal up to more than 90% are necessary to produce the final geometry. This, in turn leads to a poor buy to fly ratio. New technologies, such as additive manufacturing (AM), could support traditional process chains and could enable a more resource-efficient production. However, in additive manufacturing production cycles are still long and manufacturing costs are very high, especially for larger parts. Thus, the production by AM is often limited to low quantities and smaller components. To overcome the above-mentioned disadvantages the present study proposes a hybrid manufacturing route, combining the advantages of forging and AM. The new manufacturing route could reduce the number of processing steps and forging dies, and additionally could provide efficient near-net-shape production. The presented route is based on a conventionally pre-formed forging, which does not yet have all the features of the final component. These features, such as ribs or other structural or functional geometries, will be added by additive manufacturing. The present study investigates the use of powder laser metal deposition (p-LMD) and wire-arc additive manufacturing (WAAM) for hybrid manufacturing of Ti-6Al-4V aerospace forgings.