I have a surface tension value of high viscous fluid and experimentally measured contact angle. Can I use the Neumann equation of state to calculate the surface free energy of the substrate?
The most popular method for determining surface free energy is to measure contact angles. For the measurements, pure liquids with known surface tensions are utilized.
The force tensiometer can be used to measure surface free energy, although sessile drop measurements are the most common method.
to use relational equation with contact force,
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