Lead Free Buzzers

We are thrilled to share our latest lead-free innovation at PUI Audio with enhanced piezoelectric properties as we continue to set the standard for cutting-edge audio solutions. Our latest Piezoelectric benders and buzzers utilize Potassium Sodium Niobate, K0.5Na0.5NbO3 (KNN), a material widely recognized by researchers as among the most feasible lead-free alternatives to highly efficient, lead-based Piezoelectric Lead Zirconate Titanate (PZT).

We have various lead-free benders designed with a range of resonant frequencies and mounting configurations, and we are excited to launch a series of new audio buzzers to expand our environmentally sustainable portfolio. Our new lead-free products exhibit a strong piezoelectric effect, even with a slimmer profile. This advancement opens possibilities in the medical, industrial, automotive, and consumer sectors to provide alerts without requiring any regulatory exemptions!

Our new devices adhere to RoHS compliance without any exemptions, which is crucial in medical as well as other sensitive applications.

Material behind lead-free piezoelectric?

For decades, Lead zirconate titanate (PZT) has been the most common ferroelectric ceramic widely used for audio buzzers due to its strong piezoelectric response. PZT is composed of lead and zirconium, combined with titanate. It is formed under extremely high temperatures and is highly regarded for its superior sensitivity and higher operating temperature compared to other piezoelectric ceramics.

Potassium Sodium Niobate (KNN) is the alternate material to replace PZT used in traditional audio devices. The main challenges, up until recently, in creating leadfree piezoelectric materials include understanding the fundamental processes, the temperature sensitivity of the desired piezoelectric response, and developing compositions conducive to easy fabrication. Oxides originating from Potassium Sodium Niobate exhibit favorable characteristics, such as a high Curie temperature and environmental compatibility.

Conventional high-temperature heat treatment processes for KNN-based piezoceramics may inadvertently compromise their piezoelectric response due to the volatility of potassium and sodium ions. Researchers have now uncovered an alternative method called two-step sintering (TSS), aimed at reducing the volatilization of alkali metals. TSS involves initially exposing the ceramic to high temperatures for a short duration, followed by rapid cooling to a lower temperature for a prolonged period.

PUI Audio is proud to state that our lead-free ceramics undergo a robust established manufacturing process to demonstrate excellent piezoelectric response for the end-applications.