PI Ceramic is now offering lead-free piezoceramics to its customers: In particular the bismuth sodium titanate (BNT) and potassium sodium niobate (KNN) material systems now provide similar characteristics to the classic lead (plumbum) zirconate titanate (PZT) system in some applications. Because the lead-free alternatives behave differently than PZT ceramics, the voltage, current, or geometric dimensions of the components usually need to be adjusted, and the long-term stability and response to environmental influences must also be assessed for each application.
For several years, we have been conducting research into the possible applications of the BNT and KNN materials systems. We are pleased to offer our customers for the first time the ability to develop lead-free components for their systems on a larger scale.
Successful Applications to Date
Both material systems can be an alternative, especially in resonant applications. BNT materials are particularly suitable for thickness oscillation applications and show good performance in air bubble detection and flow sensor technology. The PI Ceramic BNT materials feature a high depolarization temperature. Unlike many other materials on the market, they can be processed with low-melting solder or thermosetting adhesives. KNN components can also be easily soldered and bonded, but also have good planar properties compared to BNT components. They are therefore used in airborne ultrasonic sensors, power ultrasonic transducers, nebulizer units, multilayer actuators, and ultrasonic motors.
More Environmentally Friendly Alternatives
Although the PZT material system is still considered the gold standard for performance and reliability in most piezoelectric applications, the demand for alternatives is increasing, particularly in medical applications. In addition, the European Commission's Restriction of Hazardous Substances (RoHS) Directive is pushing the use of lead-free materials to reduce the use of environmentally hazardous substances and prevent pollution.
Contact persons:
Sandra Niederschuh, Product Marketing Manager
Franziska Buch, Team Lead of Marketing Piezo Technology