No abstract

No abstract

AY2Si3O10 (A=Sr, Ba) trisilicate ceramics were synthesized by traditional high temperature solid state reaction method. X-ray diffraction patterns and Rietveld refinement revealed that AY2Si3O10 (A=Sr, Ba) ceramics belonged to triclinic and monoclinic crystal systems with P and P21/m space groups, respectively. The vibrational modes of [SiO4] tetrahedra, [YO6] octahedra and [(Sr/Ba)O8] polyhedra were analyzed by Raman spectroscopy. The infrared spectroscopy fitting analysis was used to determine intrinsic dielectric properties. Excellent microwave dielectric properties were measured for SrY2Si3O10 and BaY2Si3O10 with r = 9.

Cold sintering process was successfully employed to fabricate (1-x) Li 2 MoO 4-xMg 2 SiO 4 (LMO-xMSO) microwave dielectric ceramics for 5G enabled technology. Dense LMO-xMSO ceramics were obtained with a high relative density in the range of 85-100% under the conditions of 200 • C and 500 MPa in an hour. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and Raman spectroscopy showed that both the LMO and MSO phases co-exist in all composite ceramics, and that there is no detectable secondary phase. Composites of LMO-xMSO (0 < x < 0.3) resonated at microwave frequency (∼9 GHz) with a low relative permittivity (ε r) of 5.05∼5.3, and a high microwave quality factor (Q × f) of 9,450∼24,320 GHz, which are attractive for the applications of 5G enabled components.

No abstract