The US Department of Energy presented Surmet of Burlington, with a Phase I SBIR program named Durable ALON Windows for High Power RF Accelerator Applications. ALON (Aluminum Oxynitride) is a synthetic ceramic which includes mechanical, electrical, physical, chemical and optical properties.
It is transparent from the ultra-violet (UV) mid-wave infrared (MWIR), in a polycrystalline form and can be produced using traditional powder processing techniques in complex geometries.
Surmet is the sole manufacturer of ALON Optical Ceramic, which originates with the synthesis of ALON powder, proceeds with the construction of green bodies, then is heat-treated to form condensed optical blanks and the subsequent fabrication of those blanks into optical components. The company also produces ALON ‘by the ton’, mainly for Transparent Armor and Precision Optical Applications. In association with Thomas Jefferson National Laboratory, ALON Optical Ceramic will be estimated as a high power RF window material to replace the current ‘opaque’ alumina window, featuring thermal conductivity and expansion coefficient, and dielectric properties measuring down to liquid helium temperatures, prolonging its current database from -1500 C to lower temperatures as 20K. With low loss tangent and high strength, ALON windows are also transparent and facilitate the superconducting cavities to be viewed during testing and operation. This project’s characteristic feature involves combining ALON Windows with metallic ‘retaining’ structures, with hermetic seals intended to operate at cryogenic temperatures.