Extensive domain wall contribution to strain in a (K,Na)NbO3-based lead-free piezoceramics quantified from high energy X-ray diffraction

The origins of high piezoelectric properties in the lead-free (K,Na)NbO3-based tetragonal composition (K0.44Na0.52Li0.04)(Nb0.86Ta0.10Sb0.04)O-3 (KNL-NTS) is investigated by quantifying the intrinsic and extrinsic contributions from high energy X-ray diffraction measurements. The applied methodology, which allows discerning between the intrinsic contribution, related to the field induced lattice distortion, and the extrinsic contributions, related to non-180 degrees domain wall motion, is widely described in this work. The non -180 degrees domain reorientation of the KNL-NTS piezoceramic is quantify from the integrated intensities of the 002 and 200 reflections obtained from line profile, while the shifts in peak position versus the applied electric field is used to obtain the lattice strain contribution. Large non-180 degrees domain wall contribution to the electric field induced macroscopic strain (similar to 80% of the macroscopic strain) is verified in KNL-NTS. (C) 2016 Elsevier Ltd. All rights reserved.