First fundamentally new lubricant in decades created from liquid crystals

First fundamentally new lubricant in decades created from liquid crystals
The parallel ordering of liquid crystals make them near-frictionless lubricants (Image: Minutemen/Wikimedia)
The parallel ordering of liquid crystals make them near-frictionless lubricants (Image: Minutemen/Wikimedia)
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The parallel ordering of liquid crystals make them near-frictionless lubricants (Image: Minutemen/Wikimedia)
The parallel ordering of liquid crystals make them near-frictionless lubricants (Image: Minutemen/Wikimedia)

The world uses tens of millions of tons of lubricant every year, from the smallest part of a micro-precision instrument to the expansion rollers on the largest bridges. Most are oil based, though others use powders, and even metals, and it’s been that way for decades. That could be changing as the Fraunhofer Institute for Mechanics of Materials (IWM), Nematel GmbH, and Dr. Tillwich GmbH have developed a new class of lubricants that are based on liquid crystals instead of oil. According to Fraunhofer, this is the first fundamentally new lubricant developed in twenty years.

Liquid crystals are an oddity of the chemical world that most people know from digital displays and television sets, but are actually found in everything from cell membranes to soapy water. As the name implies, a liquid crystal is a substance that is neither entirely a liquid, nor a crystal, but possesses the properties of both, such as a liquid that retains the structure of a solid crystal.

It’s this structure that provides the new lubricant with its slippery quality. In a normal liquid, the molecules lay about in a random fashion, but a liquid crystal can line up its molecules in parallel, so when two surfaces are coated with a liquid crystal lubricant, they slide past one another as if on a set of microscopic rails that are nearly frictionless.

According to Fraunhofer, the new lubricants demonstrated very low friction surprisingly early in the tests, with the lubricant layers showing a high level of stability and very low wear thanks to the long, thin nature of the molecules. Testing was done using lasers designed to measure extremely low friction coefficients without having to make contact.

Fraunhofer hasn't released much about the specifics of the new liquid crystal lubricants, but the company says that the research team has been working with additives to increase the lubricant’s stability, as well as studying the chemical mechanism involved in ultra-low frictional coefficients and the adding together of different liquid crystal molecules. They've also been testing the lubricant in sliding bearings made of iron, copper, and ceramic.

Despite progress, Fraunhofer says that there’s still a long way to go before the new lubricant is suitable for practical applications. It isn't enough for a lubricant to just be slippery. It also needs to work in both high and low temperatures, have a reasonably high viscosity index, be thermally and hydraulically stable, and resist oxidation amongst other things.

When the project wound up, the team had created a liquid crystalline lubricant prototype that performed best in sliding bearings made of iron.The team is currently working on developing sliding bearings using the liquid crystal lubricant for small electric motors for the car industry.

Source: Fraunhofer

Alan Ross
A this technology could help renewable energy to power those electric cars?
Mel Tisdale
The obvious question is: "How 'sticky' is it when the crystals are in a random arrangement, i.e. not aligned as a lubricant?" It might be very useful in holding components in place until needed, such as a camera dolly, etc.
Ralf Biernacki
@Mel: Clever. An electrically controllable lubricant---OFF and it slides, ON and it binds. I'm wondering how fast the switching frequency could get. Wish I thought of that first :-)
Strange how many of these catchy articles end up with the catchy "but", "needs work", "Despite progress"..... Oh well hope springs enternal.
I recollect an article in a British science mag which discussed an Iodine based lubricant being used on a specially built engine made of metals which normally seized after a revolution or two. When using the Iodine additive the engine ran for hundreds of hours without wear.
The reasoning was that every time a metal-metal fusion took place, the iodine formed an amalgam, thus replacing the metal -metal with an iodine iodine interface and the latter had extremely low friction.
Can anybody recollect anything of this?
@ rberns - Google is your friend my friend. Though I'm not willing to pay the $42 for the document.
or if you like techno babble
Ralf Biernacki
@Galane: The babbit bearings have replaceable linings, so they can be retrofitted with another material to match the lubricant. But I do agree it would be nicer if you could just replace the oil. This is not out of the question; this material is new, and if it catches on, is likely to see gradual improvements in time.
Or perhaps not so gradual. Keep in mind that what they are using are slightly tweaked liquid crystals that were developed for a whole different use, in electronic display panels. Their key properties are optical (e.g. strong polarization of light) and electrical (e.g. fast switching). If this catches on, we can expect to see a whole new family of liquid crystal materials, engineered for their _mechanical_ properties instead.
@beergas: Your expectations of an instant breakthrough are naive. Any new technical idea needs development and refinement. Perhaps in the 18th century, at the start of the Industrial Revolution, you could just have a bright idea and presto: the thing was ready for industrial use. But I suspect not even then. Testing, prototyping, improving, gradual adoption, fitting into the existing tech base, finding and eliminating weak spots---all these are unavoidable in any new technology.
Unrealistic expectations like yours are shaped by the consumer electronics industry, with their planned obsolescence and equally planned roll-out of "new" products. But the long development process is still there, only hidden: they keep the seminal breakthroughs quiet, and only switch on the hype when they have a product ready to market. This is a deliberate illusion, and the actual road from discovery to product is long and full of setbacks.