Sensor Technology Ltd.’s BM500 series of piezoelectric ceramics contains three soft PZT formulations. They are all Navy Type materials; BM500, BM527 and BM532 correspond to Navy Type II, Navy Type V and Navy Type VI respectively. The BM500 series ceramics are lead zirconate titanate and, in general, offer high coupling coefficients and large piezoelectric charge constants. However, each piezoelectric ceramic offers some unique performance property, described below.
BM500 is the piezoelectric ceramic of choice for the majority of passive sensor applications. We use it for most of our hydrophone designs. In general, PZT-5 materials are the best choice for converting a mechanical input into an electrical signal. For example, in the case of a hydrophone, the ceramic converts an incoming pressure wave into a voltage output.
BM500 can also be used for transmission, which makes it useful for send/receive hydrophone designs. However, it has a high dissipation factor which leads to electrical losses and potentially damaging heat build-up. It is suitable only for low duty cycle, low power transmission applications.
BM532 is a modified version of BM500. It has significant increases in both the dielectric and piezoelectric charge constants (i.e. d constants). As a result, it is the piezoelectric ceramic of choice for actuator applications requiring large mechanical displacements.
It is sometimes selected for use in circuits requiring a high capacitance ceramic. For example, despite its high dissipation factor is sometimes used for small, battery powered transmit applications.
BM527 has dielectric and d constants larger than BM500 but smaller than BM532. It provides a compromise between the two materials.
Download the Safety Data Sheet (SDS) for Sensor Technology Ltd.’s piezoelectric ceramic materials. The SDS supersedes the Material Safety Data Sheet (MSDS).