Special Properties of Composite Materials of Alkaline Earth Element Oxide Compounds

The paper presents the results of experimental studies of the electrophysical properties of composite materials based on aluminate and barium titanate oxide compounds. According to standard methods, samples of aluminate-titanate-barium cement were synthesized and studied, and its main parameters characterizing ferroelectric and piezoelectric materials were determined: dielectric constant, dielectric loss, electrical resistance, Curie point, and piezoelectric modulus. Of the known dual compounds formed in this system, barium aluminate (BaAl<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>O<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</inf>) and barium titanate (BaTiO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf>) are of considerable interest from the point of view of obtaining cements with enhanced electrophysical properties. The influence of the mineralogical composition of the cement under study on its electrophysical properties was investigated. It was determined that cements containing 60–95 wt. % of barium titanate. A rational cement composition was chosen - 5% BaAl<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>O<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</inf>+ 95% BaTiO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf>. Cements with a lower content of barium titanate are characterised by reduced ferroelectricity. The dielectric loss tangent of aluminate-titanate-barium cement increases with the increase in the content of barium aluminate. The cement's Curie point has been determined and is 120°C. The piezoelectric modulus of the cement samples under consideration is higher, the higher the content of barium titanate in the cement, which is a carrier of piezoelectric properties. The study makes it possible to effectively use composite materials based on oxide compounds of aluminate and barium titanate in the production of ferroelectric and piezoelectric ceramics.