Millions of skillets notwithstanding, the slickest stuff in the world is not Teflon - and the Guinness Book of Records is, you might say, sliding back from its former position on the matter.
The 1995 edition of Guinness will bestow the title of slipperiest dry substance - as opposed to wet materials like grease and oil - on something called Hi-T-Lube, a material developed in the 1960s for use in the U.S. space program. Previous editions had accorded the honor to duPont's Teflon.The owner of Hi-T-Lube is a Linden, N.J., firm called General Magnaplate Corp. The company issued a news release announcing that its stuff had knocked Teflon from the top of the world's scale of slickness.
General Magnaplate officers pointed out that Hi-T-Lube is also some of the toughest stuff you'll ever run across, able to withstand pressures of up to 150,000 pounds per square inch and endure temperatures ranging from minus-350 degrees Fahrenheit to over 1,000 degrees.
Walter Alina, vice president of the company, said Hi-T-Lube was originally developed by New Jersey inventor Charles P. Covino for use on spacecraft parts thatcould not be lubricated with grease or oil because wet substances would boil away in the vacuum of space.
It is produced by electrically depositing several layers of metal alloys and dry lubricants onto the gears, pistons, chains, bearings, ball joints and other industrial things on which it is now used.
And how slick is Hi-T-Lube?
This slick: If two metal objects that have been plated with Hi-T-Lube are stacked on each other at an incline of only 2 degrees - that's so close to a level surface that the human eye cannot detect the slope - the one on top will immediately start to slide off.
Physicists measure that sort of thing with a value they call the "coefficient of friction" (COF). That means the relationship between two forces: the force necessary to move one surface over another and the force that presses the two surfaces together.
A simple way to measure COF is to tilt the two surfaces. The angle of incline at which the top surface starts to slide reveals the COF, Alina explained.
He said that two years ago he was browsing through a 1992 edition Guinness when he noticed the "slipperiest" listing for Teflon. The listing said Teflon had a COF .02.
He knew there was something wrong with that. A thing's slipperiness cannot be expressed in terms of one surface. Slickness cannot be observed in isolation but only in terms of how two surfaces interact.
He wrote to Guinness and asked editors to explain what they meant. They replied that they meant that Teflon had a COF of .02 when two Teflon surfaces were slid across each other.
That couldn't be true, the persistent Alina decided, because Teflon's just not that slippery. A COF of .02 means that two surfaces will slip at an incline of only slightly over one degree. When the 1994 edition of Guinness appeared, Teflon was still listed as slipperiest, but with a COF of .04.
Reading that, Alina wrote again, informing the Guinness Book of Records of a substance called Hi-T-Lube, COF .03.