(AlCrMoTaTi)N coatings were deposited on Si substrates via reactive magnetron sputtering. The effects of N2-to-total (N2 + Ar) flow ratio (RN) on the coating structure and properties were examined. Alloy coatings have composite equiaxed grain structures consisting of amorphous and body-centered cubic crystal phases, whereas nitride coatings have columnar structures with single face-centered cubic crystal phase. Distinct lattice expansion and grain refinement were observed in nitride coatings as RN increased. Typical V-shaped columnar structures with faceted tops and open column boundaries transformed into denser and smaller columnar structures with domed surfaces. Increasing RN to 30% caused the hardness and modulus to reach maximum values of 30.6 and 291.6 GPa, respectively. Electrical resistivity increased from 536 μΩ cm to 8212 μΩ cm when RN increased from 10% to 50%.
