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 epsilonrS (dimensionless) in Stress-charge form.
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Relative Permittivity epsilonrT (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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Loss factor for elasticity matrix cE, eta_cE, or loss factor for elasticity matrix sE, eta_sE: required when Mechanical Damping is present. The latter is valid only in Strain-Charge form.
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Loss factor for electrical permittivity matrix εrS, eta_epsilonS, or Loss factor for electrical permittivity matrix εrT, eta_epsilonT: required when Dielectric Loss is present. The latter is valid only in Strain-Charge form.
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Loss factor for coupling matrix e, eta_eES, or loss factor for coupling matrix d, eta_dET: required when Coupling Loss is present. The latter is valid only in Strain-Charge form.
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Electrical conductivity sigma (SI unit: S/m): required when Conduction Loss is present.
Working with Materials and Piezoelectric Materials Library in the COMSOL Multiphysics Reference Manual.