Abstract
© 2022Building multilayer architecture is an effective path to improve comprehensive properties of Al-containing nitride coatings. Here, the cubic TiAlN insertion layers are introduced to stabilize their cubic growth of TiAlBN layers through a multilayer architecture of ML_1 (Ti0.42Al0.54B0.04N/Ti0.54Al0.46N) and ML_2 (Ti0.36Al0.55B0.09N/Ti0.54Al0.46N). Based on the template effect of cubic Ti0.54Al0.46N layer, ML_1 and ML_2 multilayers exhibit coherent interfaces between B-containing and Ti0.54Al0.46N sublayers, and thereby an overall single phase cubic structure. Meanwhile, compared to Ti0.36Al0.55B0.09N with hardness of 23.0 ± 0.6 GPa, our multilayers exhibit more exceptional hardness values of 32.4 ± 0.7 GPa for ML_1 and 36.2 ± 0.9 GPa for ML_2 due to the overall cubic growth and coherent interface strengthen effect. Besides, ML_1 and ML_2 reveal better age-hardening effect during annealing process whose hardness reach 34.7 ± 1.0 GPa for ML_1 at 900 °C, and 37.6 ± 0.6 GPa for ML_2 at 800 °C, respectively. The oxidation resistance of our B-containing coatings, which is significantly better than Ti0.54Al0.46N, depends largely on the average B content. After oxidation of 10 h at 850 °C, the oxide scales of B-containing coatings are ~1.12 μm for Ti0.42Al0.54B0.04N, ~0.56 μm for Ti0.36Al0.55B0.09N, ~3.27 μm for ML_1 and ~2.74 μm for ML_2, respectively, whereas the Ti0.54Al0.46N has been fully oxidized.
NSTL