Effects of stoichiometry and substrate temperature on the mechanical properties of (ZrxTa1_x)By films

Abstract

(ZrxTa1_x)By films with various stoichiometric ratios (y) and Zr/(Zr + Ta) ratios (x) were fabricated through cosputtering by using ZrB2 and Ta or TaB2 targets. The crystallinity of the fabricated films changed from amorphous to nanocrystalline and then crystalline as the stoichiometric ratio was increased, with these changes accompanied by improvements in the films' mechanical properties. Moreover, the hardness of nearstoichiometric (ZrxTa1_x)By films was enhanced to 36.6 GPa by increasing the substrate temperature to 400 degrees C during the deposition process. This process resulted in the crystal morphology changing from a nanoscale granular structure to a columnar structure. A Cr interlayer improved the adhesion of the aforementioned films to SUS304 stainless-steel substrates, and a soft CrN top layer enhanced the wear resistance of the (ZrxTa1_x)By/Cr/ SUS304 assembly.