Finite-element modelling of thermo-mechanical stress distribution in laser beam ceramic tile grout sealing process

Abstract

Laser tile grout sealing is a special process in which voids between the adjoining ceramic tiles are sealed by a laser beam. This process has been developed by Lawrence and Li using a customized grout material and a high power diode laser (HPDL). The process has been optimally carried out at laser powers of 60–120 W and at scanning speeds of 3–15 mm/s. Modelling of the laser tile grout sealing process is a complex task as it involves a moving laser beam and five different materials: glazed enamel, grout material, ceramic tile, epoxy bedding, and ordinary Portland cement substrate. This article presents the finite element model (FEM) of the laser tile grout sealing process. The main aim of this model is to accurately predict the thermo-mechanical stress distribution induced by the HPDL beam in the process. For an accurate representation of the process, the laser was modelled as a moving heat source. A three-dimensional transient thermal analysis was carried out to determine the temperature distribution. Temperature-dependent material properties and latent heat effects, due to melting and solidification of the glazed enamel, were taken into account in the FEM, thereby allowing a more realistic and accurate thermal analysis. The results of the thermal analysis were used as an input for the stress analysis with temperature-dependent mechanical properties. The results obtained from the FEM are compared with the published experimental results.

Understanding the effect of non-conventional laser beam geometry on material processing by finite-element modelling

“…Once the displacement field due to temperature gradients in the material is known, the corresponding strain and stress fields can be calculated. Further details of the mathematical formulation are given in reference [33].…”