From fuselages and wings, to the fenders of a Chevrolet Corvette, to armor panels on military vehicles, composite materials are showing up with greater frequency in a wide range of applications.

But cutting and trimming composites is no easy task. The material is susceptible to oxidation and degradation from excessive heat. Carbon fibers don't cut well because they fracture instead of shearing smoothly.

It is largely for this reason that waterjet cutting is emerging as one of the fastest growing machine tool segments today. Having grown more accurate as a technology and offering non-contact cutting, waterjet has spread from aerospace and defense into job shops, electronics and the stone and tile industry.

"The biggest benefit waterjet has, regardless of whatever it's cutting, is that it's a non-contact cutting method with the absence of heat," says Dick LeBlanc, executive vice president at waterjet technology manufacturer Flow International. "You can machine thin to very thick metals with an abrasive waterjet and there are no metallurgical changes to the material. It's a cold-cutting process."

Abrasive waterjet cutting refers to a method of using water pressurized up to 94,000 pounds per square inch with a garnet abrasive entrained in the jet stream. The water is forced through a precision orifice up to 0.0015 inches in diameter. The water and abrasive garnet -- think of the material used on sandpaper -- cut materials with surprising speed, hitting accuracies of up to 0.001 inches.

Abrasive waterjet cutting, uses water pressurized as high as 94,000 pounds per square inch with a garnet abrasive entrained in the jet stream.

"Five or 10 years ago, that accuracy wasn't possible," says Adam Wysuph, an applications engineer at Mitsubishi. "A lot of people used waterjet as a roughing operation, then machined the part later. But today you can make finished parts from it, with a smoother edge and better quality than from a laser or plasma table."

When waterjet cutting first emerged commercially around 1985, its early embracers came from the defense and commercial aircraft industries.

"Defense was the first area of heavy use for not just composites, but they started looking for alternative methods for cutting exotic metals, such as titanium, nickels, and various alloys," says Wysuph.

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