Custom fixtures can be used to isolate and insulate medical components and magnetic resonance imaging equipment during high-temperature brazing processes. MTC-Wesgo/Duramic Alumina fixtures have both simple and intricate features, including small-diameter holes. They feature excellent dimensional stability at high temperatures (greater than 800°C) and a long service life. Also, braze material does not stick to Alumina as it does to other nonceramic materials. Alumina is an economical alternative to molybdenum or tungsten. The fixtures can be machined to tight tolerances to meet customer requirements. During the brazing process, thermal expansion of the fixture is matched to that of the Alumina insulator used for ceramic-to-metal seals. Cleanliness is ensured through a specially designed air firing process. Morgan Technical Ceramics, Fairfield, NJ, 800/433-0638.