| contents | news | events | advertisers | website | e-newsletter |
Scalmalloy
Scalmalloy® is too expensive and design optimisation only makes sense in aerospace. True or false? Additive Manufacturing is not a cheap production process. The software, machine time, materials and expertise required to make the most of the technology all come at a significant cost. The resulting financial pressures may give rise to the temptation to select a material on its price and view advanced topology optimisation as a luxury. As Jon Meyer, APWORKS, and John Barnes, The Barnes Group Advisors, demonstrate, the unique capabilities of AM mean that basing material choice on cost without considering the impact of material performance on the mass of the part is a false economy, limiting the competitiveness of AM and the potential of an application.
“Unobtanium, way too expensive…” These are common expressions you may hear regarding scandium – if someone has even heard of it. Light metals materials engineers fantasise about the potential of the element as an alloying ingredient in alloys such as aluminium. It was Soviet scientists who developed the first scandium-containing alloys and then, decades later, engineers at Airbus came up with a second-generation alloy called Scalmalloy®. In AM, metal powders are often said to be expensive, and Scalmalloy is not an exception. But the reality is that in AM, the powder cost is typically less than 15% of the overall part cost, even when considering only the mandatory post-processing (heat treatment, support removal, blasting); if Scalmalloy is going to be successful, then AM is surely the best manufacturing method to use what is considered to be an expensive material, being so efficient in material usage. Scandium has often been compared to the unicorn of elements, and known primarily to materials engineers in aerospace
Vol. 5 No. 1 © 2019 Inovar Communications Ltd
and high-end sporting goods. At 21 on the Periodic Table, it sits next to a very popular element, titanium, and yet very few people have ever heard of scandium. For those that have heard of it, they often believe that it is rare, expensive, but good when alloyed with aluminium (Fig. 2). As an element, scandium is not actually all that rare. Scandium oxide is found as a mineral all over the
Earth’s crust, and estimates place it as somewhere between the 16th and 26th most abundant element on Earth [1]. It is not found in very high concentrations anywhere and occurs naturally as complex chemical compounds (ores) or as scandium oxide hidden in bauxite, also often with other high-value metal deposits such as cobalt, platinum and premium metals. Recently, methods
Fig. 1 This Light Rider electric motorcycle from APWORKS features an additively manufactured Scalmalloy frame
Metal Additive Manufacturing | Spring 2019
127