Orientation dependence of magnetoelectric coefficient in rhombohedral Pb(Zr0.6Ti0.4)O3-cubic CoFe2O4 composite

Abstract

In this study, orientation dependences of magnetoelectric coefficient αE33 along arbitrary directions were investigated in 3 m Pb(Zr0.6Ti0.4)O3 (PZT60/40) - m3m CoFe2O4 (CFO) composites with 2–2, 1–3 pm, and 1–3 m/p connectivities using coordinate transformation method. Orientation dependences of parameters of elastic, dielectric, piezoelectric, permeability, and piezomagnetic properties for PZT60/40 and CFO were investigated independently to finally obtain anisotropy characteristics of the magnetoelectric coefficient of composites. Orientation dependence of αE33 in composites is found mainly determined by that of d31 and e31 of PZT60/40 and q31 of CFO for all three investigated connectivities. The greatly enhanced αE33’ of composites along specific orientations of piezoelectric/magnetostrictive phases were presented, which lies in: PZT60/40 ∣∣ [100] - CFO ∣∣ [001] combination for 2–2 laminate (f = 0.43, αE33 = 81 mV cm−1 Oe), PZT60/40 ∣∣ [001] - CFO ∣∣ [001] combination for both 1–3 p/m (f = 0.6, αE33 = 125 mV cm−1 Oe) and 1–3 m/p fiber composites (f = 0.6, αE33 = 121 mV cm−1 Oe). Volume fraction fmax is found unchanged when various orientations of piezoelectric or magnetic phases were applied. The results suggest that the magnetoelectric coefficient of multiferroic composites with various connectivities could be significantly enhanced by adopting specific orientations.