The incorporation of a fourth element in Ti_1-xAl_xN, like Ta, and a multilayer architecture are possible concepts to further enhance the coating performance in cutting applications. In the present study, both concepts are combined, focusing on the investigation of the microstructure and the fracture properties of two Ti_1-x-yAl_xTa_yN single layer coatings (Ti_0.55Al_0.44Ta_0.01N and Ti_0.33Al_0.54Ta_0.13N) and two corresponding multilayer coatings with the same bilayer thickness but an inverse layer sequence with different layer thicknesses. Energy dispersive X-Ray spectroscopy was utilized to determine the average composition of the coatings, confirming that the Al and Ta contents increase from single layer Ti_0.55Al_0.44Ta_0.01N via the two multilayers to single layer Ti_0.33Al_0.54Ta_0.13N. The residual stress and microstructure were studied using X-ray diffraction and scanning electron microscopy revealing higher compressive stress and grain refinement with higher Al and Ta content, which provoked an increasing hardness as evidenced by nanoindentation experiments. In contrast, the contribution of the multilayer architecture to the hardness increase is only minor. Additionally, micromechanical bending tests revealed a trend of higher fracture stress with increasing Al and Ta content. The fracture toughness was constant for all coatings as different toughening mechanisms occur.

_{在 Ti 1-x} Al _x N中加入第四种元素（如 Ta）和多层结构是进一步提高切削应用中涂层性能的可能概念。在本研究中，将这两个概念结合起来，重点研究了两种 Ti _1-xy Al _x Ta _y N 单层涂层（Ti _0.55 Al _0.44 Ta _0.01 N 和 Ti _0.33 Al _0.54 Ta _{0.13 ）的显微组织和断裂性能。}N）和两个相应的多层涂层，具有相同的双层厚度，但具有不同层厚度的反向层顺序。利用能量色散 X 射线光谱确定涂层的平均成分，证实 Al 和 Ta 含量从单层 Ti _0.55 Al _0.44 Ta _0.01 N 通过两层增加到单层 Ti _0.33 Al _{0.5 4} Ta _{0.1 3}N. 使用 X 射线衍射和扫描电子显微镜研究残余应力和微观结构，结果表明，随着 Al 和 Ta 含量的增加，压缩应力和晶粒细化程度更高，纳米压痕实验证明了硬度增加。相比之下，多层结构对硬度增加的贡献很小。此外，微机械弯曲试验表明，随着 Al 和 Ta 含量的增加，断裂应力会增加。由于出现不同的增韧机制，所有涂层的断裂韧性都是恒定的。