Indirect measurement and diagnostics of the tool wear for ceramics micro-milling optimisation

Based on their favourable mechanical features, applications of ceramics are continuously spreading in industrial environment. Such a good feature is their resistance against heat shock, so, currently they are applied e.g. as coating material for gas turbines. The paper proposes an indirect method for supervision of the cutting tool wear in the optimisation of a micro-milling process of ceramics. It replaces the expensive and time consuming measurement of the cutting tool wear in which the experiment have to be stopped, the tool has to be taken from the machine and it has to be measured e.g. by microscope. The replaced measurement has also the disadvantage that the tool has to be positioned (again) when putting it back to the machine bringing also inaccuracies to the machining. Experiments show that the proposed novel technique allows monitoring the tool wearing process characteristics without measuring the tool directly, even if the applied indirect measurement (on the workpiece) incorporates some inaccuracies. The introduced methodology supported the ceramics milling technology optimisation according to tool live and machining process time, simultaneously.