Spacecraft blast through Earth's warm, humid atmosphere to carry delicate instruments into the cryogenic vacuum of space. Arriving at their distant coordinates in the void, the instruments must respond accurately to commands from Earth to make fine adjustments in their orientation from time to time. That puts quite a demand on the lubricants, for instance, in a space telescope, which has to move very precisely indeed, to peer into distances not visible from the ground.

Researches at Rensselaer and the University of Florida will test nanotube arrays for use in tribological coatings suitable for the depths of space.

Researchers at Rensselaer Polytechnic Institute in Troy, N.Y., and at the University of Florida in Gainesville have embarked on a five-year research project funded by the U.S. Department of Defense to develop new generations of lubricants that can withstand the rigors of extreme environments.

Linda Schadler, professor of materials engineering who leads the Rensselaer team, said the group is working to develop a variety of lubricant coatings for components such as slip rings for electrical contacts, and bearings for antenna pointing systems, gyroscopes, and inertial wheels.

Thierry Blanchet, associate professor of mechanical engineering at Rensselaer, said the group will focus on developing composite coatings with nanoscale components that can meet the needs of wear resistance and low friction. Blanchet will conduct macro-scale wear tests of the new coatings when they are developed.

Research is still in the very early stages, but will cover three broad categories of materials that can be used as solid lubricants. The group is researching polytetrafluoroethylene composite containing nanoscale particles of alumina.

Another focus will be ceramic composites, formed by mixing polymer precursors to synthesize ceramic composites. The third possibility is a composite lubricant coating consisting of inclusions of nanoscale wear-resistant boron nitride particles within a matrix of silicon carbide. The coating could be applied as a thin film.

The researchers will investigate the friction and wear behaviors of carbon nanotubes that could be embedded in a ceramic matrix. Testing of the solid lubricants will take place at Rensselaer and the University of Florida.

We all hear that a new one sweeps clean. Okay, so that takes care of the floor. But what about the broom itself? If you're sweeping up in a pharmaceutical factory or a food processing plant, it had better be clean indeed, or everyone from the sweeper to the boss could wind up in hot water.

That's why Niels Sorensen, co-owner of HP-Industrial A/S, wanted to develop a new industrial broom handle, one that would eliminate areas where bacteria can lodge and grow.

Long-fiber glass-reinforced polypropylene broom handle has strength and rigidity, and resists heat and chemicals that keep it hygienically clean.

The company, a manufacturer of professional cleaning tools in Skovby, Denmark, came up with a plan: a one-piece broom handle with no joints or seams, and with a smooth and completely sealed surface, so there would be no pores for microbes to hide in. The handle had to be strong and rigid. It also had to resist chemicals and heat, and withstand repeated cleaning with steam, solvents, and disinfectants.

The company's engineers worked with RTP Co. of Winona, Minn., to find a material that would do the job and meet U.S. Food and Drug Administration requirements, to ensure that the material would be safe for food and pharmaceutical applications. They chose a long-fiber glass-reinforced polypropylene.

According to RTP, the long glass fibers absorb energy and distribute loads more evenly throughout the resin matrix. The result, according to the company, is the strength needed for the application. The highly filled compound, 50 percent glass fiber, is formulated for high flow to fill the long, narrow injection mold cavity in which the one-piece broom handle is formed.

HP-Industrial makes the mold in-house, according to Sorensen. The handle is gated at one end and molded over a steel core to produce a hollow tube. The injection mold has a flow length of 2 meters by 3.2 cm, with a consistent wall thickness of 2 mm throughout the handle. The polypropylene forms a smooth surface, with no visible evidence of reinforcing fibers, Sorensen said. "Our handles are totally straight when ejected from the mold without any warp and almost without shrinkage," he added.

HP-Industrial markets the broomstick as "the ultimate hygiene handle." It makes them in different threads and grips, and in five colors so plants can set up separate, coded cleaning zones, each with its designated tools.

When Mercury Marine in Fond du Lac, Wis., developed its new Verado in-line six-cylinder outboard motor, the company needed a new type of cowl to fit the engine's tall, narrow design. The company's typical cowls consist of two parts: a top cowl that covers the engine and a lower cowl to cover the drive train. In this case, according to Mitesh Sheth, materials engineer for Mercury Marine, adapting the previous design would have made the engine cowl too large and cumbersome for the boat operator to handle.

Mercury Marine designed a multi-part engine cowl of nylon and ionomer for its Verado outboard engine.

The company decided on a multi-part cowl that would provide easier access to the engine. A team designed a six-part injection-molded cowl using a combination of nylon and ionomer resins supplied by DuPont Engineering Polymers. The multi-part cowl weighed and cost less than Mercury Marine's earlier cowl models, which were usually compression molded from thermoset sheet molding compound or thermoformed of multi-layer acrylic and polycarbonate sheet. The new cowls require fewer secondary operations than SMC or thermoformed sheet, Sheth said.

The top and rear cowls are molded of 33 percent glass-filled nylon, providing stiffness and strength. The top cowl is a large injection molded part measuring 33.5 inches front to back, 22.9 inches across, and 16.4 inches deep, and weighing 11.3 pounds. The rear cowl is molded of a combination of mineral- and glass-reinforced nylon. The lower cowling consists of two mating parts of ionomer that achieves a high gloss finish and has good resistance to oil that could splash up from the water. The parts are injection molded by Bemis Manufacturing Co. of Sheboygan Falls, Wis.

Sheth claimed that the injection-molded assembly weighs 30 percent less than cowls formed of sheet molding compound. Tooling is more expensive for injection molding than for earlier methods, but Mercury Marine estimated that it cut costs nearly 50 percent by reducing secondary operations and decoration costs. Painting yields are typically low with sheet molding compound because of porosity and defects known as solvent popping, caused by outgassing during the painting process, which may require repair or multiple passes. The nylon parts are painted with a three-coat system achieving yields of 95 percent or better at each stage, while the lower cowls of ionomer use molded-in color that needs no painting.

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