Journals Proceedings

Abstract

In this paper, the effects of Cr3+concentrations on some physical properties and pyroelectric properties of the ceramic system of (1-x)Pb(Zr0.825Ti0.175)O3– xCr2O3, where x = 0; 0.50; 0.75; 1.00; 1.25; 1.50; 2.00% mol have been presented. Experimental results indicated that Cr3+ concentrations are of great effect on the mentioned above physical properties of the ceramics. X-ray diffraction diagrams indicated that exist pure perovskite phases with rhombohedral structure in all of ceramic compositions of the system. From SEM images we can see that rhombohedral grains of 2 m size closely arranged with small pores. Besides, ceramic densities, dielectric constants, dielectric loss factor are presented with respective values of  = 7.48 g/cm3, /0 = 343, tan= 0.03 for the optimal Cr2O3 concentration of 1.25% mol. Cr3+ concentrations are of very strong effect on structure, microstructure and electric property of the studied system. The electric conductivity are of very small values  = 2.96.10-18Ω-1 cm. Hysteresis loops are of typical rectangular form characterizing ferroelectric materials with permanent polarization Pr = (11.9 – 30.4) C/cm2 and coercive field Ec = 9.5 – 12.4 kV/cm; Pyroelectric effects are very strong in all compositions of the studied system with maximal pyroelectric coefficients γmax =(0.78 – 7.72 ).10-2 μC.cm-2.K-1, pyroelectric coefficients at room temperature (3060K) γroom = (0.15 – 0.94).10-3 μ C.cm-3.K-1