We know the big molecule names — those that put the staples in our digestive tract and the sparkle in our cars — but in the world of metallurgy, there are materials that quietly revolutionise industries without ever becoming household names. One unsung hero from this class has been Nimonic 90, a superalloy that has been improving what’s possible in high temperature applications for decades. This remarkable alloy, welded so quietly and quietly from roaring engines of jetcraft to searing heat of industrial furnaces, has quietly been getting up to the job, enduring temperatures and stresses which would reduce lesser materials to molten puddles.
The Birth of a Superalloy
Nimonic 90 did not fall out of the blue. Or, more precisely, it’s the result of years of development and research, spawned by the need for materials that can stand up to the rigours of flight in gas turbine engines. The Nimonic 90 is one of a group of nickel chromium cobalt alloys developed in the UK by the Mond Nickel Company (later Special Metals Corporation) helping to push aerospace and power generation technology forwards.
What’s in a Name?
The ‘Nimonic’ part of the name comes from the nickel-molybdenum combination that forms the base of these alloys. The ’90’ doesn’t refer to its composition percentages, as you might think, but rather to its place in the development sequence of Nimonic alloys. It’s a bit like the old Chanel No. 5 perfume – it’s not the fifth version, it’s just the one that worked best!
The Secret Sauce: Composition and Properties
Then what makes Nimonic 90 so special? It’s all in the mix. It consists of (about 60%) of nickel, with substantial amounts of chromium (about 20%) and cobalt (about 15%), among other minor impurities. The rest is carefully balanced titanium/ aluminium blend that makes it so unique.
Strength Under Fire
Its ability to maintain strength at high temperatures is one of the features of Nimonic 90 that stands out from the crowd. Of course, a lot of metals go jelly on the heat, but Nimonic 90 stays cool (figuratively speaking) at 900C and above. This high temperature strength is important for applications which are potential failing applications such as in aircraft engines or power turbines.
Corrosion? No Thanks!
However, strength is not the only thing. Nimonic 90 is also very resistant to corrosion and oxidation. It means it can tolerate both high temperatures and the usually hostile chemical environments encountered in industrial applications. It’s like having a bodyguard that’s both tough and impervious to insults.
Where You’ll Find Nimonic 90
Nimonic 90 may not be on the shelves of your nearest DIY store, but you’re unlikely to find it doing anything less than what it really should, and that is working hard in some of the most demanding environments imaginable.
Up in the Air
Nimonic 90 is used in critical components of gas turbine engines in the aerospace industry. Thinks turbine blades, discs, and combustion chamber parts. When you decide to jet off on holiday the next time, spare a thought for the Nimonic 90 who are keeping you in the air.
Down to Earth
Nimonic 90 is a star performer in power generation back on terra-firma. Industrial gas turbines rely on it to keep the lights on in people’s homes and businesses around the UK. Its ability to repeat heating and cooling cycles makes it invaluable in heat treatment equipment, as well.
The Future of Nimonic 90
Because as we push the boundaries of our technology – demanding more efficiency and performance from our machines – materials like Nimonic 90 become increasingly important. Its properties are still researched to make them better and to find new uses.
Beyond the Skies
Even nuclear fusion reactor talk involves using superalloys like Nimonic 90. If we ever crack the code of fusion power, Nimonic 90 may even be the original container for an artificial sun.
Wrapping Up
Since its creation in a British laboratory, Nimonic 90 has made the jump from its modest origins to playing a critical part in modern life. It may never be something you could ever hold in your hands, but it’s got an impact on your life.
When the next jet engine roars as it bucks up its ideas to break the sound barrier, or the light switch snaps as you flick it on behind your work desk, spare a thought for Nimonic 90 – The unsung hero of the high temperature world. It sure isn’t flashy, but in the world of engineering it’s pure gold.