@article{Ma2026, 
author = {Xiao Ma and Zhihao Dong and Weichen Zhang and Ying Jiang and Xu Cheng and Limin Guo and Peiyao Zhao and Xiaohui Wang},
title = {Ultrahigh electric field-induced asymmetric strain in Mn-doped KNN piezoceramics sintered in reducing atmosphere},
year = {2026},
journal = {Journal of Materiomics},
volume = {12},
number = {4},
keywords = {Defect, Reducing atmosphere, Electrostrain, Piezoelectric ceramics, (K,Na)NbO3-Based ceramics},
url = {https://www.sciopen.com/article/10.1016/j.jmat.2026.101248},
doi = {10.1016/j.jmat.2026.101248},
abstract = {Piezoelectric actuators are widely used industrial electronic devices. In recent years, driven by environmental concerns, lead-free piezoelectric materials, particularly KNN-based ceramics, have gained increasing attention. In this study, Mn-doped KNN piezoelectric ceramics were synthesized by the conventional solid-state reaction method and sintered in a reducing atmosphere. By employing a synergistic strategy involving defect dipoles and ferroelectric domain switching, a giant converse piezoelectric coefficient (d33*) of 2676 pm/V and a strain of 0.67% are achieved in the KNNM ceramics under an electric field of 2.5 kV/mm. In our ceramic samples, no obvious strain enhancement attributable to electrobending is observed. The ceramic exhibits excellent thermal stability, with performance degradation of less than 10% from room temperature to 170 ℃, and maintains favorable performance after 2 million fatigue cycles. Considering the combination of excellent piezoelectric properties, high temperature stability, superior fatigue resistance, and reduction resistance, KNNM ceramics are expected to facilitate the development of lead-free piezoelectric actuators compatible with base-metal internal electrodes.}
}