Corundum-type Fe-doped cathodic arc evaporated Al-Cr-O coatings

A quaternary alloying approach comprising the addition of 1-5 at.% Fe to Al0.7Cr0.3 targets for cathodic arc evaporation at 550 °C is investigated regarding its influence on promoting single-phase α-(Al,Cr)2O3 film growth. Based on detailed X-ray diffraction and transmission electron microscopy studies we can show that the α-phase fraction correlates with the incorporated Fe content and continuously extends with increasing film thickness at the expense of the cubic phases.