Down to the Wire for Metal Additive Manufacturing
Sep 16, 2020 Dr Richard Collins
Metal powders are the most common feedstock used in metal additive manufacturing. There are lots of application and scope for using powder but also barriers in rate, scale, cost, and other factors like safety, re-use, and supply chain maturity. Alternative wire feedstocks are gaining traction in the market; many directed energy deposition (DED) methods with a range of energy sources are emerging to unlock this potential.
Wire feedstocks are an attractive prospect expanding from the welding industry, the material costs are very low and as this predominantly operates through a DED process the scales and rates can be vastly improved. To differentiate themselves from the competition, new entrants are very quick to state they have a new process (and give it a new name) adding to complexity and confusion in the market. IDTechEx has rectified this with a simplified categorisation of printing processes, highlighting the differences within each when appropriate. All wire feedstock processes are similar, with the material fed through and an energy source administered; the energy source can be an electron beam (EBAM), laser, plasma, wire arc (WAAM), or with resistance welding (joule).
This area has more new hardware entrants than any other form of metal AM. The IDTechEx Research report "Metal Additive Manufacturing 2020-2030" benchmarks these processes against other forms and includes over 50 company profiles, many central to this wire-based technology ranging from enabling software for large robotic welding arms through to cheap desktop variants.
Summary of material feedstock options for metal additive manufacturing, with wire feedstocks highlighted. For more information see the IDTechEx Research report "Metal Additive Manufacturing 2020-2030" (www.idtechex.com/MetalAM)
For most, the key advantages to the approach with wire feedstocks is scale, rate, and safety. Unlike the incumbent powder bed fusion these can printer heads on large robotic arms, there is no challenge with fine powder in the atmosphere and the material can be deposited far faster. There are other powder processes pushing the deposition rate, with metal binder jetting the most prominent in targeting high-volume applications.
So, what is the problem? The main problem is precision; these printers are nearly all designed to produce near net shape parts (depending on the application) meaning that some additional machining is required afterwards. This, obviously, undermines a key advantage for additive manufacturing.
Despite this there are plenty of use-cases and notable projects. By far the most notable for this is the role that Norsk Titanium play in the delivery of certain structural parts for the Boeing 787, with considerable savings on the buy-to-fly ratio. The large scale means that many are being explored for the likes of tooling or other very low-volume large parts.
This is just the beginning for wire based DED processes. It will not compete with powder bed fusion, or other processes, on many frontiers but rather expand the industry into new directions. There are a large number of new entrants, from various backgrounds, and as it will take time to travel along the learning curve and find the economically viable applications (all with the COVID-19 backdrop) many will struggle to survive. This emerging area within metal additive manufacturing is one to watch.
For more information on the industry, all the processes, the material portfolio, and key company profiles see the report "Metal Additive Manufacturing 2020-2030" from IDTechEx Research. This includes granular market forecasts with technical insights for different alloys, processes, applications, and geography.
For more information on this report, please visit www.idtechex.com/MetalAM or for the full portfolio of Additive Manufacturing research available from IDTechEx please visit www.IDTechEx.com/research/3D.