Impact wear-resistance of Ti-Cr-B-N coatings produced by pulsed CAE of ceramic target

Abstract

Abstract Ti–Cr–B–N coatings were successfully deposited using reactive pulsed cathodic arc evaporation (CAE) of ceramic TiCrB target. The influence of the substrate negative bias voltage on the coating impact wear resistance and mechanical properties has been studied. Structural investigations have been carried out using X-ray diffraction analysis, transmission and scanning electron microscopy, glow-discharge optical-emission spectroscopy, and optical profilometry. The coating properties have been estimated by impact tests, scratch-test, and nanoindentation. The obtained results show that the coatings consist of Ti(Cr)N fcc phase with crystallites 1–2 nm in size and amorphous BNx tissure. The coatings obtained at Ubias=-250 V demonstrated highest hardness of 24 GPa, whereas samples deposited at Ubias=-500V exhibited minimal wear rate (worn area of 12 μm2) in impact conditions. Coatings obtained by pulsed CAE with intensive ion-bombardment possess high adhesion strength higher than 120 N.