Materials manufacturers may soon be producing dense, heat-resistant, complex ceramics cheaper and easier with the recently patented "displacive compensation of porosity" method or DCP technique. "There are several advantages of our method," says inventor Kenneth Sandhage of the Materials Science and Engineering Department at The Ohio State University. The DCP process avoids extensive shrinkage in the processing of dense ceramic parts, works at lower temperatures than conventional methods, does not require the use of high pressures, and eliminates the need for post-process ceramic machining. Sandhage starts with ceramic powder to make a porous preform. Then, researchers soak the preform in a liquid metal alloy bath. "The preform absorbs the liquid metal like a sponge, and the liquid metal then reacts with the ceramic powder to form a new ceramic compound that fills in pore spaces," says Sandhage. The result is a part with a larger internal solid volume, but the exact same external shape and dimensions as the original preform. The DCP method requires reaction temperatures of only 1,200 to 1,300C, compared to the 2,000C required for traditional methods, to form very high melting point, covalently-bonded ceramics. "The DCP-derived composites are very light too," he continues. Immediate applications for such carbide-rich composite materials include machine tools, body armor, and rocket nozzles. Sandhage is working with MetaMateria Partners (Columbus, OH), which will act as an intermediary to further develop the technology. Once prototypes are available, MetaMateria will look for licensing opportunities with other companies. For more information, contact J. Richard Schorr at (614) 340-1690 or e-mail: firstname.lastname@example.org.
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