Breakthrough in Zero Friction Materials

You've heard of superc conductivity, but have you heard of its cousin? Super lubricity. Superconductivity means zero electric resistance. Super lubricity means zero friction. Sounds like an advert for a frying pan, but it's much bigger than this. Imagine the ultimately smooth surface and how that would change the world. Okay, I know it's hard to imagine, but give me a few minutes and I'll try to explain why it would be big and also what's behind the recent headlines claiming that a research group in China achieved near zero friction on macroscopic scales. This episode of our science news is supported by Mel Science. That's a subscription service for science experiments that I personally enjoy a lot. And of course, I have a special offer for you. Meroscience has lovely experiment sets for children and young learners. They cover physics, chemistry, and STEM in general. Each kit includes the equipment and stepbystep instructions. This kit, for example, explores magnetic levitation. I find magnets eternally fascinating. They are such a clear example for how forces invisibly extend through space. It's not just that magnets have so many practical applications from magnetic levitation to microphones. It's also one of the four fundamental forces of nature. It's a great gift for curious kids who love learning by doing. And it's also a great basis for further exploration. And here comes the special offer. If you use the link in the info below and the code zabin year, you'll get a year of science for just $22. 45 45 per month until March 21st. And now back to the science news. Friction is everywhere all the time. Friction is why we can walk and why cars can drive. It's why you can lift a glass and write with a pen. Without friction, your muscles wouldn't contract and your blood wouldn't properly clump. Friction is part of our life whether we want that or not. But just like electrical resistance, friction wastes a lot of energy. Every time a motor turns, every time a fridge pumps cooling liquid, every time a turbine makes another turn, friction creates heat, which wastes energy. And it's not just the direct loss of energy during operation. It's also that friction causes wear, which means you must replace parts, gears, pistons, fan, all these gradually wear down. For engineers, friction can be a headache. It's not just engineering. A remarkable example for what a difference low friction materials can make comes from the swimming competition of the 2008 Olympics in Beijing. That year, several contestants came with new high-tech swimsuits made from ultra smooth water repellent fabric rather than the traditional swimwear material. These suits were designed to significantly reduce friction with the water that in return decreased turbulence and saved the swimmers energy so they could move faster. 23 world records fell because of this. After lots of debate, the International Swimming Federation banned the suits for most competitions. I honestly found that very disappointing because for me the technological advances that help athletes run faster, jump higher, or hit stronger are as remarkable as the rest of their performance. But fine, no supersuits. Let's return to engineering and the new paper. The authors have shown that it's possible to make two solid objects slide past each other with almost no friction. The material they used isn't anything fancy. It's graphite, the same stuff that pencils use. Graphite is made of many extremely thin sheets stacked on top of each other. Those sheets can slide easily, which is why pencils work. The authors of the new paper grew very pure graphite crystals with almost no defects. Then they peeled off flakes that are about a tenth of a millimeter wide, and those they showed slide over each other with almost zero friction. The reason this didn't work previously was simply that it's difficult to grow the graphite purely enough. You might say, "Okay, but a tenth of a millimeter isn't exactly large. " Well, for one thing, that is quite large for microscopic devices. It's also much larger than the previous demonstrations. You might also remember the superconductor experiments that were literally working with tiny crumbs. So this is at a similar lab level. Their no friction material has a peculiar feature though which is that the friction depends on how the atomic latises in the two surfaces are aligned. For some angles friction is low, for some it's

high. This might come in useful for some applications, but it's still not the universal no friction coating we're hoping for. This, of course, is not the only recent development in frictionless research. I'm just using this paper as an excuse to tell you something about this. There are other groups working on other materials, and not just that, but also on how to make those materials more durable and easier to produce. It's easy to underestimate this sort of research, but this isn't a niche interest. Low friction coatings are a billion dollar market and the market is projected to almost double in the next 10 years. I know this isn't the sort of sexy fundamental physics breakthroughs that people seem to be drawn to, but I think that material science is one of the most underrated research areas. You don't have to take my word for it. If you look at what artificial intelligence startups want to do in research, material science is at the top of the list. Why? It's because there is a quiet revolution in material design that most of the world is entirely missing. And the people who work on those startups understand that there is a lot of money to make there. It's not just surface coatings to reduce friction. It's better electrical or optical behavior, selfhealing cracks, intelligent responses to temperature or pressure change and so on. Not flashy, just world changing slowly without drama and with very little friction. Thanks for watching. See you tomorrow.