Journal of Electroceramics

, Volume 18, Issue 3–4, pp 251–253 | Cite as

A Piezoelectric-Metal-Cavity (PMC) actuator

  • K. H. LamEmail author
  • C. L. Sun
  • H. L. W. Chan
  • X. Z. Zhao
  • C. L. Choy


A novel piezoelectric-metal-cavity (PMC) actuator has been designed to exhibit a large flexural displacement. This PMC actuator consists of a metal ring sandwiched between two identical piezoelectric unimorphs. The radial contraction of the piezoelectric ceramic is converted into flextensional motion of the unimorph, causing a large flexural displacement in the centre part of the actuator. The metal cavity acts a function of circumferential coupling of the piezoelectric unimorphs. It was found that the effective piezoelectric charge coefficient of the PMC actuator can approach 40,000 pC/N. With its high piezoelectric and electromechanical coupling coefficients, the PMC actuator gives a static displacement 16 μm can be produced under a d.c. driving voltage of ±77 V.


Piezoelectric Actuator Unimorph 



This work was supported by the Centre for Smart Materials of the Hong Kong Polytechnic University.


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Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  • K. H. Lam
    • 1
    Email author
  • C. L. Sun
    • 1
    • 2
  • H. L. W. Chan
    • 1
  • X. Z. Zhao
    • 2
  • C. L. Choy
    • 1
  1. 1.Department of Applied Physics and Materials Research CentreThe Hong Kong Polytechnic UniversityHunghom, KowloonChina
  2. 2.Department of PhysicsWuhan UniversityWuhanChina

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