The influence of a high power diode laser (HPDL) generated glaze on the wetting characteristics and the subsequent HPDL enamelling of ordinary Portland cement

High power diode laser (HPDL) surface glazing of the ordinary Portland cement (OPC) surface of concrete was found to effect significant changes in the wettability characteristics of the OPC. This behaviour was identified as being primarily due to: (i) the polar component of the OPC surface energy increasing after HPDL glazing from 3.46 to 15.56 mJ m−2; (ii) the surface roughness of the OPC decreasing from an Ra value of 21.91 to 2.88 μm after HPDL glazing; and (iii) the relative surface O2 content of the OPC increasing by 4.5 at.% after HPDL glazing. HPDL glazing was consequently identified as occasioning a decrease in the enamel contact angle from an initial value of 109–31°, thus allowing the vitreous enamel to wet the OPC surface.