High-entropy coatings produced by electron-beam deposition of multicomponent Al‒Ni‒Co‒Fe‒Cr‒Ti‒B_x (x = 0, 0.25, 0.5, and 1 mol) powder mixtures onto steel substrates in vacuum were examined. The effect of boron content on the phase composition, structure, and strength properties of the AlNiCoFeCrTiB_x coatings was studied employing X-ray diffraction, microstructural analysis, and micromechanical tests. The AlNiCoFeCrTi and AlNiCoFeCrTiB_0.25 coatings showed a typical dendritic and interdendritic structure and consisted of two substitutional solid solutions with a body-centered cubic (bcc) structure, differing in lattice parameters. An increase in the boron content to 0.5 mol changed the phase composition and led to the formation of in-situ titanium diboride TiB₂ as fine inclusions and chromium boride Cr₂B as elongated inclusions in the coatings besides the two bcc solid solutions (bcc1 and bcc2). When 1 mol of boron was added, the coatings remained four-phase, while the amount and sizes of TiB₂ and Cr₂B inclusions increased. Moreover, with 1 mol of boron, the ratio between the bcc1 and bcc2 phases increased toward bcc2 because of the removal of chromium and titanium atoms. Mechanical tests showed that the microhardness and yield stress of the AlNiCoFeCrTiB_x coatings produced by electron-beam deposition increased by 1.6 times when boron content raised to 1 mol: from 8.8 and 2.4 GPa for the AlNiCoFeCrTi coatings to 14.2 and 4 GPa for the AlNiCoFeCrTiB coatings. The significant enhancement in the strength indicators (hardness and yield stress) of the high-entropy coatings with greater boron content could be attributed to the solid-solution strengthening effect of interstitial boron atoms and to the strengthening effect of boride phase inclusions.

多组分 Al-Ni-Co-Fe-Cr-Ti-B 电子束沉积高熵涂层_x (对真空中钢基材上的粉末混合物（x = 0、0.25、0.5 和 1 mol）进行了检查。采用X射线衍射、显微组织分析和表征手段，研究了硼含量对AlNiCoFeCrTiB_x涂层物相组成、结构和强度性能的影响。微观机械测试。 AlNiCoFeCrTi和AlNiCoFeCrTiB_0.25涂层表现出典型的枝晶和枝晶间结构，由两种具有体心立方（bcc）结构的替代固溶体组成，不同的在晶格参数中。硼含量增加至 0.5 mol 改变了相组成，导致原位形成细小的夹杂物形式的二硼化钛 TiB₂ 和硼化铬除了两种 bcc 固溶体（bcc1 和 bcc2）之外，Cr₂B 作为拉长夹杂物存在于涂层中。当添加1 mol硼时，涂层保持四相，而TiB₂和CrB夹杂物增加。此外，当硼含量为 1 mol 时，由于铬和钛原子的去除，bcc1 和 bcc2 相之间的比例向 bcc2 方向增加。力学测试表明，当硼含量增加到1 mol时，电子束沉积AlNiCoFeCrTiB_x涂层的显微硬度和屈服应力提高了1.6倍：从 AlNiCoFeCrTi 涂层的 8.8 和 2.4 GPa 到 AlNiCoFeCrTiB 涂层的 14.2 和 4 GPa。硼含量较高的高熵涂层强度指标（硬度和屈服应力）显着提高，这可能归因于间隙硼原子的固溶强化作用和硼化物相夹杂物的强化作用。