The influences of surface roughness on the water contact angle for coated substrate with F-DLC

Hydrophobicity improvement of DLC can be achieved by adding fluorine element usually. However, higher F content may affect the other performance of DLC seriously, such as strength and abrasive resistance. Plasma enhanced chemical vapor deposition technology were employed to prepare F-DLC on the surface of steel (S35C) substrate in condition of 20mass% of F. Experimental results demonstrated that roughness significant increase in the coating substrate has contributed to improve hydrophobicity. In the range of 0∼200nm for the roughness, the contact angle is influenced by the surface energy and the surface roughness; Ra>200nm, the influence of roughness on the water contact angle is gradually becoming the leading. And Ra=1300nm, water contact angle is 104°. © 2018 Trans Tech Publications, Switzerland.