This doctoral work represents a contribution to the development of science in the field of laser-assisted milling (LAMill). LAMill is implemented in the processing of a hard-to-machine ceramics, based on zinc oxide (ZnO). Damage formation in this material during LAMill is characterized and a strategy for varistor machining is developed. The influential process parameters are identified and the interactions between these are determined. Analytical modelling of heat transfer when heating the workpiece by a laser has been studied and an analytical thermal model is developed to solve the problem of accurate temperature prediction near the workpiece edge during LAMill with low computational power requirements. Empirical models to predict more complex process variables are developed and verified. The possibility of empirical modelling using neural networks is explored and the effectiveness of this approach is compared to the established linear modelling approach with ANOVA. Our findings show that the damage during processing of this material is formed by initiation and propagation of intergranular cracks. Two main process parameters affecting damage formation were identified, feed-per-tooth fz and temperature of the material ahead of the cutting zone, T. Increasing T initially inhibits the spread of intergranular cracks, but a new mechanism that leads to the formation of new cracks was identified at higher T. Increasing fz leads to an extended amount of damage on the machined surface. Edge chipping can’t be controlled using the proposed strategy.
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