The Effect of Technological Production Conditions on the Ability of AlN–Y2O3–С-Based Composite Materials to Absorb Microwave Radiation

New composite materials based on AlN–Y2O3–С have been created for use as absorbers of microwave radiation in vacuum electronics. X-ray diffraction and structural studies have shown that the major phases in the structure of the composites are AlN (hexagonal and cubic), Y3Al5O12, Al3O4, and С. An increase of time of component mixing and grinding influenced structure formation, promoted an increase in the content of the Al3O4 phase, and led to enhancement of microwave radiation attenuation by the composites (from 6.5 to 7.6 dB), this being indicative of an increase in the absorption capacity of the ceramics obtained.