Nanoscale coatings

Ames Laboratory scientist Bruce Cook is leading an effort to develop nanoscale coatings to boost the energy efficiency and extend the life of pump rotors and industrial cutting tools.

The coating Cook is investigating is a boron-aluminium-magnesium (BAM) ceramic alloy called AlMgB14 that he discovered with Alan Russell, a fellow Ames Laboratory researcher and Iowa State University (ISU) professor of Materials Science and Engineering, about eight years ago.

Working with ISU materials scientist Alan Constant, Cook’s team is using pulsed laser deposition to deposit a thin layer of the alloy on hydraulic pump vanes and tungsten carbide cutting tools.

Cook is also working with Eaton Corporation, a manufacturer of fluid power equipment, using another, more commercial deposition technique known as magnetron sputtering, to lay down a wear-resistant coating.

Initial tests show a decrease in friction relative to an uncoated surface of at least an order of magnitude with the AlMgB14-based coating.

In preliminary tests, the coating also appears to outperform other coatings such as diamond-like carbon and TiB2.

Pumps aren’t the only applications for the boride nanocoatings.

The group is also working with Greenleaf Corporation, an industrial cutting tool maker, to put a longer-lasting coating on cutting tools.

If a tool cuts with reduced friction, less applied force is needed which translates to a reduction in the energy required for the machining operation.

A photograph of the process of coating a substrate (left) with AlMgB14 by pulsed laser deposition. The bright plume in the centre of the photograph is an AlMgB14 plasma. The solid target is just to the right of the plume