Estimation of the minimum material removal thickness during the polishing process of ceramic tiles by laser triangulation

The possibility of controlling the thickness to be removed from each tile during the honing/polishing process of ceramic tiles would avoid unnecessary wear of the abrasive tools, directly minimizing energy and water consumptions. Such technology requires a conveyer belt capable of adjusting the height of the tile surface, together with a measuring system to estimate the most recommendable removal depth for each tile. While the former requirement is still not promptly available in the market, the on-line characterization of the geometrical characteristics of the tiles could be theoretically performed by many techniques. In this context, this study presents the 3D micro-inspection by laser triangulation as a promising technique to be employed at the production line prior to the honing process. To verify this hypothesis, six types of surfaces with different compositions were characterized in terms of 3D topography, waviness profiles, and surface roughness. The results indicate that the methodology adopted in this study is able to provide precise information regarding the minimum layer to be individually removed from the tile surfaces. In addition, it was also observed a relationship between the surface waviness and the tile composition. In contrast to the value of ca. 10% typically adopted in most ceramic industries, for the surfaces considered in this study, the minimum removal layers were found to be between 1.08% and 2.37% of the initial thickness.