Phase Compositions And Microwave Dielectric Properties Of Nominal Al2-Xyxmo3o12 Ceramics

A convenient solid-state reaction was utilised to synthesise nominal Al2-xYxMo3O12 (0 <= x <= 0.6) and Y2Mo4O15 ceramics. The actual compositions of the nominal Al2-xYxMo3O12 ceramics are Al2Mo3O12 and Y2Mo4O15. In general, the rho(r) of ceramics with the A(2)Mo(3)O(12) (A = Al, Cr, Fe, In, Sc) structure is low when the solid-phase synthesis is adopted. However, the second phase Y2Mo4O15, which appeared in Al2-xYxMo3O12 ceramics, compensated for this shortcoming. The rho(r) of Al2-xYxMo3O12 ceramics increased from 90.39 to 96.18% when x increased from 0 to 0.1 and reached its maximum value (98.96%) when x was 0.4. Excellent microwave dielectric properties, i.e. epsilon(r) = 7.28, Q x f = 93,100 GHz and tau(f) = - 65.70 ppm/degrees C, were achieved in Al1.6Y0.4Mo3O12 ceramics. A novel microwave dielectric ceramic Y2Mo4O15 exhibited excellent microwave dielectric properties, i.e. epsilon(r) = 7.77, Q x f = 78,900 GHz and tau(f) = - 63.50 ppm/degrees C. The two ceramic materials have remarkable application value in the field of microwave components and LTCC applications.