Influence of dry micro-blasting grain quality on wear behaviour of TiAlN coated tools

The effects of Al2O3 and ZrO2 grains, in dry micro-blasting of coated cemented carbide inserts, on film's hardness and brittleness, cutting edge geometry as well as on tool life are introduced. Nanoindentations on film surfaces, at various pressures micro-blasted, revealed the influence of the different micro-blasting grains on the coating superficial hardness. For investigating the effect of the developed film compressive stresses at certain micro-blasting pressures and grain qualities on the film's brittleness, nano-impact tests were conducted. Moreover, roughness and cutting edge geometry measurements were carried out via confocal microscopy and EDX microanalyses after micro-blasting by Al2O3 or ZrO2 grains for detecting potential film thickness decrease and substrate revelation. The wear behaviour of coated and variously micro-blasted tools was investigated in milling of hardened steel. The attained results provide insight concerning optimum selection of micro-blast ing data in various grain cases, for improving the cutting performance of coated tools.