Mathematical modelling of the fibre laser surface processing of a zirconia engineering ceramic by means of three-dimensional finite-element analysis

摘要

The thermal effects of fibre laser surface treatment on a ZrO_2 engineering ceramic were studied using a computational finite-element model (FEM). Temperature increases on the surface and the bulk of the ZrO_2 during the fibre laser processing were measured using an infra-red thermometer and specifically located thermocouples. The results showed an error of 5 per cent with the surface and 18 per cent within the bulk of the ZrO_2 when comparing the experimental readings with those of the FEM. The FEM revealed a relationship between the traverse speed, power density, time, depth, and the temperature during various stages of the fibre laser surface treatment of the ZrO_2. By utilizing data obtained from a thermogravimetry-differential scanning calorimetry (TG-DSC), the FEM predictions of the temperature distribution were used to map phase transformations and significant events occurring during the fibre laser surface treatment of the ZrO_2. The mapping revealed that the fibre laser surface treatment generally resulted in a phase transformation of the ZrO_2 at various temperatures changes as further shown in the article.