May 26, 2009

Chrome coatings replaced with safer alloys

U.S. scientists say they've created a new alloy to replace chrome as a protective shiny coating, thereby eliminating the dangerous chrome industrial process.

Massachusetts Institute of Technology scientists said chrome adds beauty and durability to a wide range of metal products -- from bathroom fixtures to car bumpers -- but those products come at a heavy cost. Although cheap to produce and harmless to consumers, the scientists said the industrial process used to create chrome is dangerous for workers and pollutes the environment.

People have been trying to replace it for a very long time, said Associate Professor Christopher Schuh. The problem is that it's the only plated metal coating that has all of these properties -- hardness, long-lasting shine and corrosion protection.

However, Schuh and his colleagues have developed a new nickel-tungsten alloy that they say is not only safer than chrome, but also more durable. The new coating, which is now being tested on the bumpers of a truck fleet, might also replace chrome in faucet fixtures and engine parts, among other applications, the scientists said.

Schuh's team showed nickel-tungsten alloys remain stable indefinitely at room temperature and are highly resistant to decomposition when heated. They can also be made harder and longer lasting than chrome, which itself is harder than steel.

The research was funded by the U.S. Army Research Office.