The origin of chemical inhomogeneity in lead-free potassium sodium niobate ceramic: Competitive chemical reaction during solid-state synthesis. (1st June 2021)

• Record Type: Journal Article
• Authors: Thong, Hao-Cheng; Payne, Alexis; Li, Jia-Wang; Cheng, Yue-Yu-Shan; Jones, Jacob L.; Wang, Ke
• Is Part Of: Acta materialia. Volume 211(2021)
• Publication Date: 2021-06-01
• Subjects: Lead-free -- Potassium sodium niobate -- Ceramic -- Chemical Inhomogeneity -- Solid-state reaction; Materials -- Periodicals; Materials science -- Periodicals; Materials -- Mechanical properties -- Periodicals; Metallurgy -- Periodicals; Chemistry, Inorganic -- Periodicals; 620.112
• DOI: 10.1016/j.actamat.2021.116833
• Languages: English
• ISSNs: 1359-6454

Abstract

Abstract: Excellent electromechanical properties have been reported in lead-free potassium sodium niobate (KNN)-based piezoelectric ceramics over the past 15 years. However, poor reproducibility of the electromechanical properties of KNN has been a major barrier to industrial development, due to a lack of full understanding of some of the processing aspects. Chemical inhomogeneity is one of the most critical challenges in processing, as the properties of KNN-based ceramics are strongly composition-dependent. In the present study, in-situ temperature-dependent X-ray diffraction and thermogravimetric analysis were employed to investigate the chemical reactions that occur during solid-state synthesis. Chemical homogeneity was found to be sensitive to the competition among reactants during synthesis. The phenomenon can reasonably explain the chemical inhomogeneity in KNN and possibly other lead-free piezoelectric ceramic systems prepared via solid-state synthesis. Graphical abstract: Image, graphical abstract