Like an ancient alchemist trying to turn base metal to gold, today’s metallurgists are constantly striving to find that elusive chemical recipe that will produce an alloy with the kinds of mechanical properties our manufacturing industry is crying out for.
With governments around the world pledging to cut carbon emissions by 2035, aerospace designers have a new problem to deal with: namely specifying structural materials that require low manufacturing carbon footprints.
Many jobs could be at risk if your country fails to reach its net-zero target. Indeed, steel industry jobs are currently at the greatest risk because their manufacturing processes are dependent on burning coal at high temperatures.
Designers have employed the fictional term ‘unobtainium’ to refer to exotic or costly materials - or even when researching the development of a material that is perfect for their needs in every respect - except that it doesn’t actually exist!
Titanium remains the industry’s metal of choice, but whilst its unique high strength-to-weight ratio properties, and corrosion and temperature resistance ensure it has consolidated its future as a firm favourite, other non-metallic materials like thermoplastic composites continue to erode the metallic dominance within aerostructures.
However, exacting safety demands mean we’ll always be faced with arduous material certification requirements. Imagine a giant version of the Scales of Justice, where on one side you have a finished aircraft, and on the other a huge pile of documentation. The upshot being that the aircraft won’t fly until the documentation is the same weight as the aircraft!
Designers now live in hope that somehow base metal can eventually be turned into ‘green gold’. They still continue to look for that sweet spot; they are still eager to tap into that mother lode at the end of the runway.