Influence of modulation ratio on structure and properties of nanoscale ZrB2/ZrAlN multilayered coatings

ZrB2/ZrAlN multilayered coatings with various modulation ratios (t(ZrB2):t(ZrAlN)) and constant modulation periods were prepared by magnetron sputtering system at room temperature. SEM, XRD, surface profiler and nano-indenter were employed to investigate the influences of t(ZrB2):t(ZrAlN) on the microstructure and mechanical properties of the coatings. Sharp interfaces and nanoscale multilayered modulation were confirmed by SEM. The multilayer with modulation period of 40 nm and ratio of 3:1 displayed the highest hardness (36.4 GPa) and critical fracture load (76.477 mN) with lower stress. The polycrystalline structure and multilayered modulate structure were directly responsible for the enhanced mechanical properties.