Effect of LiF and HfO2 on the LKNNT lead-free piezoelectric ceramics

摘要

In this work, the HfO and LiF have been used to improve the piezoelectric behavior of Li(KNa)(NbTa)O(LKNNT) lead-free ceramics prepared by the conventional solid-state method. The addition of little amount HfO/LiF co-doped will not change the phase structure of LKNNT ceramics. In this study, due to the co-doping of HfO/LiF. The relative density of LKNNT can up to 98.73%, piezoelectric constant d is 347 pC/N, electric-mechanical coupling coefficient k is 48%, and relative dielectric constant ε is 2701, and tanδ = 1.3%. Therefore, it is an effective way to improve the piezoelectric properties of KNN-based ceramics by the addition of HfO and LiF.