An analysis of the bonding mechanisms active in a high power diode laser generated two-stage ceramic tile grout

It is quite possible to bring about changes in the wettability characteristics of a two-stage ceramic tile grout by means of high power diode laser (HPDL) surface treatment. Such changes manifest themselves as a reduction in the contact angle, θ, and are due to the HPDL inducing changes which reduce the surface roughness, increase the surface O 2 content and increasing the polar component of the surface energy. What is more, HPDL treatment of the two-stage ceramic tile grout surface was found to effect an improvement in the bonding characteristics by increasing the work of adhesion, W ad. Along with wettability experiments carried out with selected liquid-metals, an electronic approach was used to identify the bonding characteristics of the two-stage ceramic tile grout before and after HPDL. It is thought that HPDL induced changes to the two-stage ceramic tile grout produced a surface with a reduced bandgap energy which consequently increased W ad by increasing the electron transfer at the metal-oxide interface and thus the metal-oxide interactions. Furthermore, it was suggested that the increase in W ad of the two-stage ceramic tile grout after HPDL treatment was possibility due to a correlation existing between the wettability and ionicity of the two-stage ceramic tile grout. Here it is believed that the HPDL treated surface is less ionic in nature than the untreated surface and therefore exhibits better wettability characteristics.