Effects of P2O5/TiO2 ratio on the sintering behavior and microwave dielectric properties of TiP2O7. Issue 3 (April 2015)

• Record Type: Journal Article
• Authors: Wang, Y.N.; Bian, J.J.
• Is Part Of: Ceramics international. Volume 41:Issue 3(2015)Part B
• Page Start: 4683
• Page End: 4687
• Publication Date: 2015-04
• Subjects: TiP2O7 ceramic -- Sintering behavior -- Microwave dielectric properties; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2014.12.015
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: TiP2 O7 ceramics with various P2 O5 /TiO2 ratios were prepared by the traditional solid-state process. Constituent phases and microstructure were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Microwave dielectric properties were studied with a network analyzer in the frequency range 10–13 GHz. Although phase pure TiP2 O7 could be obtained for the stoichiometric and P-excess compositions after calcining at 900 °C, (TiO)2 P2 O7 secondary phase occurred for all compositions after sintering at 1250 °C/2 h. Phase pure TiP2 O7 ceramic could not be obtained due to the evaporation of P2 O5 at sintering temperature, although excessive P2 O5 and muffling with sacrificial powder were adopted. P-deficiency increased the amount of (TiO)2 P2 O7 impurity phase. The stoichiometric and P-excess compositions demonstrated poorer densification and hence lower dielectric permittivities but higher Qf values than those of P-deficient compositions. Good optimized microwave dielectric properties with ε r ~11, Qf ~77, 000 GHz, and τ f ~14 ppm/°C could be obtained for the stoichiometric and P-excess compositions.