Structure and mechanical properties of ZrCrAlN nanostructured thin films by closed-field unbalanced magnetron sputtering

Quaternary ZrCrAlN nanostructured thin films were synthesized by Closed-Field Unbalanced Magnetron Sputtering, and their microstructure and mechanical properties of the ZrCrAlN nanostructured thin films were examined. The grain refinement of the ZrCrAlN nanostructured thin films was controlled by adjusting the N2 partial pressure. The hardness of the film varied with the N2 partial pressure and the maximum value was approximately 45 GPa. It was also confirmed that there is a critical value of the grain size, dc, needed to maximize the hardness.