Electrical Contact
The Electrical Contact node defines correlations for the conductance h at the interface of two bodies in an imperfect contact due to the surface roughness. It can be added to pairs by selecting Pair Electrical Contact from the Pairs menu.
The conductance h is involved in the current flow across the surfaces in contact according to:
where indices 1 and 2 refer to the two sides of the boundary.
Electrical Contact
Select the Constriction conductance — Cooper-Mikic-Yovanovich correlation (the default), Mikic elastic correlation, or User defined. For User defined enter a value or expression for hc (SI unit: S/m2). The default is 0 S/m2.
Contact Surface Properties
This section displays if Cooper-Mikic-Yovanovich correlation or Mikic elastic correlation are chosen under Contact.
Enter values for the:
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Surface roughness, asperities average height σ asp (SI unit: m). The default is 1 μm.
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Surface roughness, asperities average slope masp (dimensionless). The default is 0.4.
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Contact pressure p (SI unit: Pa). The default is 0 Pa.
For Cooper-Mikic-Yovanovich correlation select a Hardness definition — Microhardness (the default), Vickers hardness, or Brinell hardness.
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For Microhardness enter a value for Hc (SI unit: Pa). The default is 3 GPa.
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For Vickers hardness enter a value for the Vickers correlation coefficient c1 (SI unit: Pa) and Vickers size index c2 (dimensionless). The defaults are 5 GPa and −0.1, respectively.
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For Brinell hardness enter a value for HB (SI unit: Pa). The default is 3 GPa. HB should be between 1.30 and 7.60 GPa.
For Mikic elastic correlation select the Contact interface Young’s modulus Econtact — Weighted harmonic mean (the default) or User defined.
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For Weighted harmonic mean, enter values or expressions for the Young’s modulus, upside, Eu (SI unit Pa), the Young’s modulus, downside, Ed (SI unit Pa), the Poisson’s ratio, upside, νu (dimensionless), and the Poisson’s ratio, downside, νd (dimensionless). If this node is selected from the Pairs menu, enter instead values or expressions for the Young’s modulus, source, Esrc (SI unit Pa), the Young’s modulus, destination, Edst (SI unit Pa), the Poisson’s ratio, source, νsrc (dimensionless), and the Poisson’s ratio, destination, νdst (dimensionless). The defaults are 0.
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For User defined enter another value or expression for the Contact interface Young’s modulus Econtact (SI unit: Pa). The default is 1 GPa.
Theory for Electrical Contact