While Scandium is relatively scarce at this time, there is significant potential for growth in trade of the metal provided supply increases. The properties of scandium-aluminum alloys in particular make the material promising for many markets.
Scandium is appealing to many industries, and the properties of scandium-aluminum alloys in particular make the material promising for many markets.
While Scandium is relatively scarce at this time, there is significant potential for growth in trade of the metal provided supply increases. If a cost-effective supply of scandium were to become available, two markets would be most likely to consume the metal at scale – solid oxide fuel cells and aluminum-scandium alloys.
Solid oxide fuel cells (SOFC)
Should scandium supply sources increase, the solid oxide fuel cell market would be able to use between two and five times the amount of scandium it currently consumes.
Fuel cells function by converting oxygen and a fuel source into an electrical current, water, carbon dioxide and heat. Theses cells include solid electrolytes made from hard ceramics for which scandium could be used as a stabilizing agent. The operation of a fuel cell is exothermic and as reactants are available and the internal environment is hot enough, the reaction will remain continuous.
Fuel cells have existed for more than a century, and NASA has used them as a power supply source on spaceships in the past. There are several types of fuel cells, but solid oxide fuel cells are currently the best in terms of efficiency, flexibility and low pollution.
Scandium is an excellent choice as the stabilizing agent for the zirconia in the solid electrolyte in solid oxide fuel cells – it’s a better electrical conductor than yttrium, which is usually used. That means the reaction within cells can take place at lower temperatures, lowering the cost of materials required for thermal shielding. Fuel cells can be used for industrial and commercial applications to produce cost-efficient electricity. There are many companies in this space today, and a good number would likely use scandium if the metal were available.
Aluminum-scandium alloys have a number of benefits including good heat tolerance and weldability as well as a strength that approaches the level of steel. Air transportation industry researchers at the EADS Group – which includes Airbus Industries, Eurocopter and ASTRIUM, among others – have been working for some time with scandium-aluminum alloys and their applications. Planes could benefit significantly from some parts being made of scandium-aluminum alloys due to the lightness and strength of the material. There is precedent for this, as Russia crafted its MIG jets from this material during the Cold War.
Another possibility would be the use of scandium-aluminum alloys in additive layer manufacturing, which prints 3D CAD models out of metal. As with other types of 3D printing, the use of scandium-aluminum alloys could potentially revolutionize parts of the manufacturing industry. In particular, scandium could be used to create custom parts at any necessary scale without significant material loss in this way. Certainly, the aluminum alloy industry would welcome any new and reliable supply of scandium.