Structural and Microstructural Characterisation of Refractory Oxides Synthesised by Laser

Abstract

Several ceramic materials have been chosen and synthesized by Selective Fusion by Laser (SFL). These materials have been selected because their refractory condition, high hardness and good colouring power, that make them useful to be used as ceramic pigments. In the present work it is shown the structural and microstructural characterisation of these materials prepared by Laser assisted synthesis, individually and into a vitreous matrix (glaze) and subjected to a firing cycle with a maximum (highest) temperature of 1200º C. The techniques used in the characterisation have been Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), thermal analysis as Differential Thermal Analysis (DTA) and Thermogravimetry (TG) and UV-Vis Spectroscopy to obtain their CIE-Lab chromatic coordinates.

Laser Engraving of Ceramic Tiles

“…The use of diode pumped lasers increases the ablation rate significantly. For example, 50 W and 100 W diode pumped lasers achieve scanning rates of 1080 and 2160 cm 2 /h and improve the ablation rates to 8.3 and 10.8 cm 3 /h, respectively 4,5,21 . As may be deduced from Fig.…”

“…Photothermal and/or photochemical interaction mechanisms tend to predominantly influence the pulsed laser interaction with materials 4–7,21 . Laser ablation occurs when the energy absorbed by the material is sufficiently intense to produce vaporization and expulsion of its outermost layers.…”

“…No significant presence of solidified melt is observed in these micrographs, consistent with the ablation scheme proposed for porcelain tiles, as discussed earlier. Published work has demonstrated the mechanical stability of these engraved tiles, which allow thermal treatments and glazing, while still keeping their optical finish characteristics 4,21 …”

“…Laser technology offers a modern tool not yet exploited in ceramic tile manufacturing, as demonstrated recently on white porcelain tiles. 4,5 The latter work presents the first demonstration of high-definition machining of ceramics for decorative purposes, and reviews the advantages of the laser and its modes of operation for decorating industrial ceramic tiles.…”

Laser-assisted production of Bi-doped silica glasses

“…Laser melt processing has been successfully applied to ceramic synthesis [9], refractory oxide eutectic growth [10], directional solidification of superconductor oxides [11][12][13], superconductor and perovskite coating formation [14][15][16] as well as surface modification of the zirconia construction ceramics [17] and an investigation of the rare earth aluminate formation [18]. Due to the fact that laser melting synthesis is a continuous process, it is easily controlled by the laser emission parameters.…”