BISMUTH SODIUM TITANATE (BNT)-BASED LEAD-FREE PIEZOELECTRIC CERAMIC COATINGS BY THERMAL SPRAYING METHOD

Abstract

Interests in rapid prototyping and directly producing sensors and electronics on engineering structures and parts have inspired the revolution of smart materials fabrication. As important smart materials, piezoelectric ceramic coatings have shown great application potentials in structure health monitoring, energy harvesting, etc. Thermal spray process has been applied for producing structural and thermal barrier ceramic coatings with the advantages of high productivity, large area coating ability, less limitation of substrates and low cost, but not established for producing piezoelectric ceramic coatings with complex compositions and perovskite structure. Bismuth sodium titanate (BNT)-based material is considered as one of the most promising lead-free piezoelectric ceramic system. In this work, BNT piezoelectric ceramic coatings with dense morphology and single perovskite phase were fabricated by thermal spray process. The melting-recrystallization behaviors of BNT ceramic were investigated. The structural evolution of the thermal sprayed BNT-based coatings and their electrical properties were examined.