Influence of zirconium substitution on dielectric, ferroelectric and field-induced strain behaviors of lead-free 0.99[Bi1/2(Na0.82K0.18)1/2(Ti1−x Zr x )O3]-0.01LiSbO3 ceramics

The Crystal structure, dielectric, ferroelectric and field-induced strain behaviors of lead-free 0.99[Bi1/2(Na0.82K0.18)1/2(Ti1−x Zr x )O3]-0.01LiSbO3 (BNKTZ-LS) ceramics were investigated in the composition range x = 0 − 0.040. XRD patterns revealed the formation of a pure perovskite phase with no apparent structural phase transition. The temperature-dependent dielectric peaks of the BNKTZ-LS ceramics broadened and the ferroelectric polarizations decreased with increasing Zr concentration. Ferroelectric and bipolar field induced-strain curves indicated a disruption of ferroelectric order upon Zr addition into the BNKT-LS ceramics. This destabilization of the ferroelectric order was accompanied by an enhanced field-induced strain. A high field-induced strain (S = 0.30%) with a normalized strain (d*33 = S max /E max = 500 pm/V) was observed at an applied electric field of 6 kV/mm at x = 0.020.