Dielectric properties of CaCu ₃Ti ₄O ₁₂/Pb(Zr _0.52Ti _0.48)O ₃ composite ceramics

A new composite ceramics of CaCu ₃Ti ₄O ₁₂/Pb(Zr _0.52Ti _0.48)O ₃ have been designed and fabricated to reduce the dielectric loss with certain higher dielectric constant. Pb(Zr _0.52Ti _0.48)O ₃ was coated on the surface of CaCu ₃Ti ₄O ₁₂ particles, and then the composite particles were sintered to obtain CaCu ₃Ti ₄O ₁₂/Pb(Zr _0.52Ti _0.48)O ₃ composite ceramics using conventional technologies which include the spark plasma sintering. The phase composition and microstructure were studied by means of X-ray diffraction and scanning electron microscopy. The result shows that the ceramics are composed of CaCu ₃Ti ₄O ₁₂, Pb(Zr _0.52Ti _0.48)O ₃ phases (this phase mainly exists at the grain boundary) and some impurities. It is also found that the grain size and the grain shape of composite ceramics are greatly affected by interfacial coating of Pb(Zr _0.52Ti _0.48)O ₃. The impedance spectrum measurement result shows that the CaCu ₃Ti ₄O ₁₂/Pb(Zr _0.52Ti _0.48)O ₃ composite ceramics with the Pb(Zr _0.52Ti _0.48)O ₃ content of 20% has the highest dielectric constant and the lowest dielectric loss.