Effect of TiO2 and Ta2O5 additions on the electrical properties of Li2CaAl4Si4O16 glass-ceramic

Influence of TiO 2 and Ta 2 O 5 on crystallisation for ceramic based on Li-Ca-Al-Si was studied. Sintering of glass-ceramics leads to the formation of β-eucryptite, anorthite and Ca-olivine. These phases are developed only on samples containing TiO 2 and Ta 2 O 5 . Incorporation of either TiO 2 or Ta 2 O 5 gives clear crystals of low pores than in the base sample. Addition of Ta 2 O 5 or TiO 2 improves densification properties and reduces sintering temperature. Electrical measurements were done in audio frequency range and lower (90 Hz-100 kHz). Composition changes on electrical properties were examined. Experimental electrical data show that the response of specimens was not simple (not a linear relation). The increase of TiO 2 and Ta 2 O 5 generally decreases the electrical properties of the ceramic specimens used in this case. Electrical properties were able to follow and interpret the change in composition. This information was correlated to the internal structure of the samples.