The thesis deals with a comparison test of aluminium alloys die cast trimming tools wear. The wear of the trimming segments with and without hard coating was examined. The serial trimming process using a hydraulic press with the segment without the coating and the segment with the coating, as well as microscopic and profile measurements are presented. Both segments were analysed before the test, after 50.000, and after 75.000 production cycles; the real production process made additional analyses impossible. After measurements and analysis, the wear comparison of both segments was examined. It was concluded that the use of hard coating did not cause any problems in the trimming process. It was concluded that the wear of the segment without coating was much more extensive than the wear of the segment with the coating. The measurements proved that the hard coating prevented the formation of build-up edges on the segment surface, and that after 50.000 production cycles the hard coating started to peel off from the basic material of the segment, and that the remaining burrs on the cutting edge could have a major influence on durability of coating. It was established that the wear of the segment with the coating even after 75.000 production cycles was smaller than the wear of the segment without the coating after 50.000 production cycles.
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