Diameter prediction of removal particles in Al^sub 2^O^sub 3^ ceramic laser cutting based on vapor-to-melt ratio

In order to predict the particle size of molten removal in laser cutting Al2O3 ceramic plate, an atomization model based on vapor-to-melt ratio is developed to reveal the relationship between material remove forms and results during the process of vaporization-melt. Model correction of vapor-to-melt ratio with different parameters is obtained by laser cutting of 96.4% Al2O3 ceramic plate to get the slit width. The experimental verification is carried out on a JK701H Nd:YAG pulse laser cutting system by simulating under the regression correction of melt flow diameter. Micro-observation on the molten particles with different plate thickness (1.5 mm, 2.0 mm, 3.0 mm varied with increasing of vapor-to-melt ratio) and the calculations show that the particle diameter decreases rapidly (70 µm, 60 µm, 35 µm) with vapor-to-melt ratio after increasing to an extreme value (80 ~ 85 µm). It is proved that there is an antagonistic relationship between kinetic and thermodynamic effect in the impact of vapor-to-melt ratio (with critical value of 0.1) on the morphology of cutting removal. The results show good agreement between atomization model and experiments with average error below 8%. The analysis verifies this model is feasible and it makes contribution to determine the reasonable processing parameters (such as the control of vapor-to-melt ratio) in laser precision cutting.