A 2-STAGE CERAMIC TILE GROUT SEALING PROCESS USING A HIGH-POWER DIODE-LASER - II - MECHANICAL, CHEMICAL AND PHYSICAL-PROPERTIES

Ceramic tiles sealed using a portable 60 Wcw high power diode laser (H PDL) and a specially developed grout material having an impermeable en amel surface glaze have been tested in order to determine the mechanic al, chemical and physical characteristics of the seals. The work showe d that the generation of the enamel surface graze resulted in a seal w ith improved mechanical and chemical properties over conventional epox y tile grouts. Both epoxy tile grout and laser generated enamel seals were tested for compressive strength, surface roughness, wear, water p ermeability and acid/alkali resistance. The enamel seal showed clear i mprovements in strength, roughness and wear, whilst being impermeable to water, and resistant (up to 80% concentration) to nitric acid, sodi um hydroxide and detergent acids. The bond strength and the rupture st rength of the enamel seal were also investigated, revealing that the e namel adhered to the new grout and the ceramic tiles with an average b ond strength of 45-60 MPa, whilst the rupture strength was comparable with the ceramic tiles themselves. The average surface roughness of th e seals and the tiles was 0.36 and 0.06 mu m, respectively, whilst. fo r the conventional epoxy grout the average surface roughness when poli shed was 3.83 mu m and in excess of 30 mu m without polishing. Life as sessment testing revealed that the enamel seals had an increase in act ual wear life of 2.9 to 30.4 times over conventional epoxy tile grout, depending upon the corrosive environment. (C) 1998 Elsevier Science L td. All rights reserved.