Contact angle and sessile drop diameter hysteresis on metal surfaces

The experimental stand to measure the static contact angle and drop diameter is presented in the paper. The results of contact angle and diameter of the drops on aluminium, brass, copper and stainless steel with different roughness are added. The measurements were done for the increasing and decreasing drop volume. As a result the hysteresis of contact angle and magnitude of wetting surface was observed. It was noticed that aluminium and stainless steel lose their hydrophobic properties during the dropping procedure while copper and brass remain the hydrophilic or hydrophobic material.