Next time you find yourself on an aeroplane speeding down a runway, perhaps on your way to somewhere hot, consider for a brief moment that the jet engines taking you there will have already reached temperatures of 1,500C (2,732F). This temperature exceeds the melting point of the metals that make up the engine, and the fact that the whole thing doesn’t just turn into a molten pool of liquid is down to some nifty materials. So remarkable are they that when they were developed in the 1940s, the heyday of comic-book superheroes, the alloys were given the name “superalloys”. Unlike their fictional counterparts, the super powers of these alloys can now be understood rationally, although at the time they were a mystery.

If you have ever blown up a balloon and then let it go, allowing it to zoom and fart its way around a room, you will have a good grasp of how a jet engine works. As your compressed breath shoots out in one direction the balloon is propelled in the opposite direction: it’s called Newton’s third law, which states that every action has an equal and opposite reaction. Fireworks and space rockets work in the same way except that they use chemical reactions to create the gas. It’s a simple but very inefficient way of producing thrust. If aircraft relied on this type of jet engine to get around, average ticket prices would be tens of thousands of pounds and the environmental impact would be devastating.

It was the British engineer Frank Whittle who worked out how to solve this problem. He reasoned as follows: the sky is already full of gas so there is no need to carry it around with you, just compress it as you go, and shoot it out the back. This required a machine to be built that sucked air in at the front, compressed it, and shot it out the back. The compressor is what you see under the wing as you board a plane – it looks like a giant fan, and it is, but what you can’t see is that behind it are 10 or more fans, each one smaller than the next. Their job is to suck in the air and compress it. In the middle of the engine is the combustion chamber where the compressed air is mixed with fuel and ignited, producing a jet of hot gas that then shoots out the back of the engine. The genius in the design is that on its way out of the engine some of its energy is used to rotate a set of turbines – it is these turbines that rotate the compressors at the front of the engine. In other words, the engine harvests energy from the hot gas to collect and compress air as it flies through the sky.

It’s a pretty neat trick, but you can immediately see the problem: the materials of the turbines have to take the full brunt of the combustion gases, which reach temperatures of more than 1,500C. Not only that, but they are rotating at tens of thousands of revolutions per minute, experiencing huge stresses. Whittle and the others looked around for answers from materials scientists. A candidate was stainless steel, which looked like it could resist the corrosive conditions inside the white-hot jet engine. But like most metals, it gets weaker as it gets hotter, losing up to 50% of its strength by the time it reaches 700C. The reason for this is that the strength of steel, like most metals, is governed by dislocations – a type of structural irregularity, like a ruck in a carpet, that moves like a Mexican wave through the crystal. As the temperature gets higher, so dislocations find it easier to move and so make the metal softer: this is why blacksmiths heat up metals before shaping them into things like horseshoes.

Whittle’s search appeared hopeless, except for the discovery of a patent that had been granted in 1929 for a very unusual nickel alloy: a combination of nickel, chrome, aluminium and titanium. For some reason, this alloy could retain almost all its strength at high temperatures. No one knew why, and they had to wait 20 years for electron microscopes good enough to see what was going on. What they found when they finally could look inside the nickel crystals was that a whole forest of other crystals had grown. In other words, there were crystals within crystals. Called gamma prime crystals, these stopped dislocations moving extremely effectively and kept doing so almost up to its melting point that was, drum roll, 1,365C.

Between 1960 and 2010 there was a 55% increase in the fuel efficiency of jet aircraft and much of this is down to improvements in these alloys: now the intricate alloy structure is beefed up by additions of exotic elements such as rhenium, tantalum and hafnium. The turbine blades are now grown as single crystals, laced with cooling channels and coated in ceramic to protect them from the gas temperatures above their melting point.

The alloys are super indeed. In my opinion, the women and men who make them, in factories such as Rolls Royce in Derby, are also super. They are the modern blacksmiths, but instead of shoeing horses for a living, they shoe turbine jet engines.