In this study, boron was introduced into TiAlN coating to improve its performance. Ti_0.44Al_0.56N, Ti_0.42Al_0.54B_0.04N, and Ti_0.36Al_0.55B_0.09N coatings were synthesized by arc evaporation, and the effect of B on structure, mechanical and thermal properties of TiAlN coatings were investigated by detailed experiments. Furthermore, we studied the formation energy (E_f) of cubic and wurtzite phases in Ti_1-x-yAl_xB_yN coatings by density functional theory (DFT) calculations.

First-principle calculations indicate that the incorporation of B reduces the solid solubility of Al in cubic TiN, which is confirmed by the experimental results. Ti_0.44Al_0.56N coatings show a face-centered cubic structure while Ti_0.42Al_0.54B_0.04N and Ti_0.36Al_0.55B_0.09N exhibit a mixed structure of cubic and wurtzite phases. In addition, experimental results show that doping B by 4 at.% gives rise to an increase in hardness from 30.1 ± 0.4 GPa of Ti_0.44Al_0.56N to 32.7 ± 0.9 GPa of Ti_0.42Al_0.54B_0.04N, while further increasing B content to 9 at.% triggers a dramatic decrease of the hardness down to 23.0 ± 0.6 GPa (Ti_0.36Al_0.55B_0.09N). Alloying with B also significantly improves the oxidation resistance of TiAlN coatings by retarding the transformation of a-TiO₂ to r-TiO₂ and promoting α-Al₂O₃ formation.

在这项研究中，将硼引入TiAlN涂层中以改善其性能。通过电弧蒸发合成了Ti _0.44 Al _0.56 N，Ti _0.42 Al _0.54 B _0.04 N和Ti _0.36 Al _0.55 B _0.09 N涂层，并通过详细的实验研究了B对TiAlN涂层结构，力学性能和热性能的影响。此外，我们通过密度泛函理论（DFT）计算研究了Ti _1-xy Al _x B _y N涂层中立方相和纤锌矿相的形成能（E _f）。

第一性原理计算表明，B的掺入降低了Al在立方TiN中的固溶度，这由实验结果证实。Ti _0.44 Al _0.56 N涂层显示_出面心立方结构，而Ti _0.42 Al _0.54 B _0.04 N和Ti _0.36 Al _0.55 B _0.09 N显示出立方相和纤锌矿相的混合结构。此外，实验结果表明，掺入4 at。％的B可使硬度从Ti _0.44 Al _0.56 N的30.1±0.4 GPa增加到Ti _0.42 Al _0.54 B _0.04的32.7±0.9 GPa当N进一步增加B含量至9 at。％时，会导致硬度急剧下降至23.0±0.6 GPa（Ti _0.36 Al _0.55 B _0.09 N）。用乙合金化也通过-TIO的转变延迟显著提高TiAlN涂层的抗氧化性₂至r-TIO ₂和促进的α-Al ₂ ö ₃形成。