Original Date: 11/03/1996
Revision Date: 01/18/2007

The Y-12 Plant at Oak Ridge has over thirty years experience making ceramic parts up to 21 inches in diameter from various materials including oxides, carbides, nitrides, cermets, salts, and beryllium and uranium materials. The objective is to make near-net shape parts with the needed properties of full density, high purity, and high strength, and as cost effective as possible.

The primary method to densify the ceramics used at Y-12 is quasi-isostatic hot pressing, accomplished by employing a furnace capable of reaching 2,500°C and determining the part shape by a high strength graphite die. Y-12 has also experimented with hot isostatic pressing using a gas autoclave that can reach temperatures of 1,000°C and 30,000 psi argon pressure. However, these processes are expensive because of low production rate and process length time.

An alternative method of densifying ceramics being developed at Y-12 is microwave sintering. This method reduces processing time up to a factor of 10, reduces processing temperatures by several hundred degrees, provides superior material properties, and can be accomplished in near-net shape. A very large microwave furnace has been developed that can reach temperatures of 2,400°C and has microwave frequencies of 2.45 and 28 GHz. Y-12 is also experimenting with variable frequency ranges to more effectively heat the part.

The ceramics manufacturing capability at Y-12 is world class as demonstrated by the numerous patents awarded to the personnel. A patent has been applied for in the microwave sintering process, and this Plant continues to advance the technology of ceramics manufacturing and become an important industrial resource for this process.

For more information see the Point of Contact for this survey.