Interaction of CO2, Nd:YAG, excimer and high power diode laser (HPDL) radiation with the surface of a common mild steel (EN8) was found to effect changes in the wettability characteristics of the steel, namely changes in the measured contact angle. These modifications are related to changes in the surface roughness, changes in the surface oxygen content and changes in the surface energy of the mild steel. The wettability characteristics of the selected mild steel could be controlled and/or modified by laser surface treatment. A correlation between the change of the wetting properties of the mild steel and the laser wavelength was found.
- surface roughness
- contact angle