New Wire Additive Manufacturing (NEWAM)

3D printing, or, Additive Manufacturing (AM), has rapidly come to prominence as a valid and convenient alternative to other production techniques, this is thanks to a growing body of evidence that its advantages in terms of lead-time reduction; design flexibility and capability; and reduced manufacturing waste are not only potential, but very much real. Metal AM techniques can be categorised based upon the form of the material they use (powder or wire), the heat source (laser, electron beam, or electric arc), or the way the material is delivered (pre-placed bed, or direct feed). Each of the metal AM technologies, given its particular properties, is best suited for specific applications. For example, the selective laser-melting of a pre-placed powder bed yields precise, net-shape components that can be very complex in design. However, their size is limited, cost is high, and build rates are low. In contrast, the Directed Energy Deposition (DED) processes can build near-net-shape parts, at many kilograms per hour, and with potentially no limitation to a components' size. To date, most of the work in wire based DED has been carried out at Cranfield University, where a 6-m-long aluminium aero-structure was built in a few days. Research over the last 10 years has also proven the capability to make large titanium parts in a timely manner (weeks instead of months) and with much reduced cost (up to 70% cheaper than machining from solid), resulting in a tremendous industry pull. However, manufacturing such components is extremely challenging; so far, it has been based on engineering principles; a great deal of empirical know-how is required for every new application, leading to long lead times and high cost for new applications and materials. These are ever-varying and numerous, in light of the heterogeneity of the end-users mix. Therefore, there is an urgent need to develop a science-based understanding of DED processing; this is key to exploit its full potential and enable the industrial pick-up it merits. Such potential could be increased by combining more than one process: E.g. an arc and a laser could be coupled into one symbiotic machine, generating a multiple energy source configuration. Our vision is to radically transform Large Area Metal Additive (LAMA) manufacturing, by pioneering: - new high build-rate wire based DED with greater precision of shape and microstructure - production of net-shape large-scale engineering structures, at low cost - guaranteed 'right-first-time' homogeneous or tailored high performance properties and structural integrity. Four universities (Cranfield U., U. of Manchester, Strathclyde U., and Coventry U.) have joined forces to deliver this ambitious research programme over five years with a budget of £7M. The LAMA programme is formed by four interconnected projects: 1. LAMA's engine room. New wire-based DED processes with two primary aims: simultaneous high build rate with precision net-shape deposition (no finishing process required); and independent thermal control from deposition shape, using active thermal profile management. 2. LAMA's design room: new wire compositions tailored to the newly available thermal process regimes, and capable of producing properties better than the equivalent forged alloys; it will also provide crucial information regarding the formation and criticality of defects. 3. LAMA's modelling room: key fundamental science and understanding, using advanced process and material modelling and state-of-the-art high efficiency techniques. Physics-based thermal and fluid-flow models, as well as microstructural and mechanical models will be developed and implemented. 4. LAMA's quality room: physics-based framework for guaranteed mechanical properties and structural integrity in as-built components; including the development of in-process non-destructive evaluation techniques. LAMA will build on and exploit the UK's substantial lead in wire-based DED technology.