Define Material Properties
Define material properties for the piezoelectric materials. The material library contains several common piezoelectric materials under the piezoelectric section. If you want to define your own piezoelectric material, you need to specify its properties by hand. The required properties depend on whether the constitutive relations are in Stress-charge or Strain-charge form, and which damping and loss attributes are created. Defining all piezoelectric settings before materials preselects the required properties and makes the completion easier:
Mechanical Properties
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Density rho (SI unit: kg/m3)
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Elasticity matrix cE (SI unit: Pa) in Stress-charge form.
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Compliance Matrix sE (SI unit: 1/Pa) in Strain-charge form.
Electrostatic Properties
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Relative Permittivity εrS (dimensionless) in Stress-charge form.
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Relative Permittivity εrT (dimensionless) in Strain-charge form.
Coupling Properties
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Coupling matrix eES (SI unit: C/m2) in Stress-Charge form.
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Coupling matrix dET (SI unit: C/N) in Strain-charge form.
Damping and Loss Properties
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Either loss factor ηcE for elasticity matrix cE, or the loss factor ηsE for compliance matrix sE: required when Mechanical Damping is present. Both are dimensionless, the latter is valid only in Strain-Charge form.
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Either loss factor for electrical permittivity matrix εrS, or loss factor for electrical permittivity matrix εrT: required when Dielectric Loss is present. TBoth are dimensionless, the latter is valid only in Strain-Charge form.
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Either loss factor ηe for coupling matrix e, or loss factor ηd for coupling matrix d: required when Coupling Loss is present. Both are dimensionless, the latter is valid only in Strain-Charge form.
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Electrical conductivity σe (SI unit: S/m): required when Conduction Loss is present.
Working with Materials and Piezoelectric Materials Library in the COMSOL Multiphysics Reference Manual.