PZT Actuators with active moisture suppression

Hermetically Sealed Piezo-ceramic Actuators

Piezo-ceramic multilayer actuators must be effectively protected against moisture to ensure reliable and lasting operation. Conventional polymer or ceramic coatings can only offer this to a certain degree. Tests have shown that leakage current greater than 1 mA already occurs here within a few seconds. CeramTec has an answer to this problem: Hermetically sealed actuators with active moisture suppression. No other company in the world offers this solution.

Piezo-ceramic multilayer actuators in a stainless steel casing are CeramTec’s answer to the moisture problem. Their casing is milled from a single piece of stainless steel and offers a 100% diffusion barrier. In fact, the casing is so dense that the actuator can even be used under water.

Thanks to its bellows design, the stainless steel casing exhibits low stiffness, which is necessary to allow the free expansion of the actuator when voltage is applied. The electrical connection wires are firmly fixed into the casing with a special glass solder. CeramTec has developed a unique process to prevent residual moisture from being trapped in the ceramic surface before and during production. Water is chemically converted after hermetic sealing to ensure a completely water-free environment inside the stainless steel casing.

Dimensions (examples), other geometries on request

Diameter (mm) Length (mm) Electrical
connection
Operation-
voltage (V)
Capacitance (μF) Free
stroke (μm)
Blocking
force (N)
13.0 38.0 Connector pins 200 1.2 45.0 900
13.0 38.0 Connector pins 150 1.9 45.0 900
13.0 38.0 Connector pins 200 2.6 45.0 1800

Worth knowing:

Hermetically sealed
PZT Actuators

  • Extremely robust mechanical design
  • Ideal for high humidity and harsh conditions
  • Extremely low leakage current even after continuous use
  • Extremely high long-term stability
  • Adjustable stroke
  • Extremely fast response in the of 0.1 ms range
  • High blocking forces – up to 1–2kN
  • Low pre-load of 30N
  • Lasting function even under water

PZT Actuators in a stainless steel Casing – Ready for new Applications

The leakage current for piezo-ceramic PZT actuators in a stainless steel casing from CeramTec is still well under 100 nA even after thousands of hours of use. This makes them the ideal actuators for all applications in high humidity environments. But there are also advantages in normal conditions as the installation does not demand any special care in the mechanical handling of these hermetically sealed actuators.

CeramTec offers a special power module for very high blocking forces to meet various customer demands. Integrating several piezo-ceramic actuators in a hermetically sealed casing ensures functional reliability in continuous operation.

Leakage current of housed actuators, typical (60%rH, 25°C)

Piezoelectric Standard Actuators

Piezoceramic actuators utilize the piezoelectric effect: A piezoceramic PZT material expands in the direction of the electrical field when voltage is applied to it. A piezoelectric actuator offers interesting solutions for micro-positioning, valve control, vibration damping and sound generation.

Piezo-ceramic Materials

Piezo-ceramics are used to convert mechanical parameters, such as pressure and acceleration, into electrical parameters or, conversely, to convert electrical signals into mechanical movement or vibration.

Recommended Contacts

Please click on the button “Contacts” to the right, to get a list with the personal and direct responsible contacts within the CeramTec Group.