Wear and tear on engine components is common because of friction and it happens in all machinery with moving parts. Lubricants that reduce friction can only delay and minimize inevitable damage. The idea of reversing that wear by fixing a worn part was a goal of Pavlo “Pasha” Rudenko, a Washington State University Ph.D. candidate who decided to research the use of smart nanoparticles to replace eroded material. Restoring damaged parts to a like-new condition was also intriguing to NASA, which awarded Rudenko a space grant to pursue the technology.
Parts that move in relative motion, either working together or against each other, will always experience friction and sooner or later, wear. When the friction between parts inhibits machine performance, lubricants are used. Many common lubricants are oil-based — mineral or plant — and contain numerous fortifying additives, without which the oil would quickly degrade. Additionally, these chemicals, dissolved or suspended in the oil, perform a variety of functions: they maximize viscosity at different temperatures, remove debris, and improve chemical stability.
Rudenko proposed creating a nanoparticle lubricant that would work at any temperature including in the extremes of space. The goal was to use an existing liquid lubricant to carry nanoparticles directly to the point of friction. He believed this solution would be ideal for satellites and space vehicles. In addition to keeping parts in good repair, such a nanofluid lubricant could extend the functional life of the systems using it. His initial research identified the best material — a type of ceramic that was effective, durable, and nontoxic.
The material, also called nano-flakes, is sticky on one side and smooth on the other. The sticky side is attracted to points of friction and attaches itself to those spots, leaving the smooth side facing out. This happens over and over, building up layers of nanoparticles until a given rough spot is smoothed over, much like filling in a pothole in a street. The heat and pressure that naturally occur with friction bond the nano-flakes together, forming a new, durable carbon-lattice surface that Rudenko calls “diamond-like.”
Even when the surface of a metal part appears smooth to the eye and touch, an atomic force microscope can reveal imperfections at the nanoparticle level that can and do create friction. With an aim toward fixing these tiny imperfections in engines, Rudenko started TriboTEX LLC in 2017 and became its chief technology officer. The first TriboTEX formula was created to work in automobiles.
Today, more than 30,000 cars and trucks are using TriboTEX. That usage data is expanding the body of evidence that synthetic nanoparticles yield the intended results. The most common benefits drivers report are improved gas mileage, increased torque, and increased oil pressure.
In cars with 130,000 miles or more, the company claims that fuel economy can be improved up to 6 percent along with increased in-cylinder compression. The particles also decrease engine noise by filling in gaps and grooves as small as 40 microns — about the width of a human hair — although they also stop building up once the gap is filled. Cars can also increase their engine power up to 3 percent, said Rudenko, noting that this is remarkable for a treatment that circumvents the cost of dismantling any part of the engine. Adding TriboTEX to a vehicle every 40,000 miles will ensure that there are enough nanoparticles available to fix new instances of wear in parts of the engine that experience significant friction.
As consumers have used TriboTEX, they’ve suggested other potential applications and the company now offers a small-engine product for use in motorcycles, lawn mowers, generators, and compact cars. A high-performance version is formulated to work in diesel trucks and large-engine sports cars. The “big rig” formula treats semi-tractor trailer engines. A national commercial trucking company is testing TriboTEX in a number of trucks in its fleet. Rudenko is also working on using nanomaterials in aviation gearboxes.
Learn more at spinoff.nasa.gov .