This paper investigates the influence of the surface orientation of TiN and Al layers, as well as TiN layer thickness on the deformation behavior and mechanical characteristic of TiN/Al bilayer composites under the nanoindentation process through molecular dynamics (MD) simulation. The result shows that the TiN(1 1 1)/Al(1 1 1) workpiece with Ti-face has the greatest loading force and hardness, indicating that the strength of this specimen is improved better than other surface orientations, and the increase in TiN layer thickness leads to increase the loading force and hardness. However, defects such as dislocation and phase transformation appear also more in the TiN(111)/Al(111) workpiece with Ti-face, while the phase transformation and the number of dislocation in the Al layer are clearly decreased as increasing the TiN layer thickness. The surface morphology reveals that the sink-in phenomenon in indents has occurred in all samples with the change of TiN/Al surface orientations. Besides, the indents appear the sink-in for TiN layer thickness from 10 Å to 30 Å, and the pile-up is present in the indentation with TiN thicknesses of 50 Å and 70 Å. The atomic zone in the high stress–strain state is focused on the interface and around the indenter in all samples, and the interface acts as a barrier against the spread of stress and strain into the substrate interior. Furthermore, the atomic area in the high-temperature state is concentrated surrounding the indenter due to the friction between the substrate and indenter, and the deformation process of material from elastic to plastic causes the heat increase in the substrate

本文通过分子动力学 (MD) 模拟研究了 TiN 和 Al 层的表面取向以及 TiN 层厚度对纳米压痕过程下 TiN/Al 双层复合材料的变形行为和机械特性的影响。结果表明，TiN(1  1  1)/Al(1  1 1) Ti-face的工件加载力和硬度最大，说明该试样的强度比其他面取向提高得更好，TiN层厚度的增加导致加载力和硬度的增加。然而，TiN(111)/Al(111) 工件在 Ti 面时，位错、相变等缺陷也出现较多，而随着 TiN 层的增加，Al 层的相变和位错数量明显减少。厚度。表面形貌表明，随着 TiN/Al 表面取向的变化，所有样品都发生了压痕下沉现象。此外，对于 10 Å 到 30 Å 的 TiN 层厚度，压痕出现下沉，并且在 TiN 厚度为 50 Å 和 70 Å 的压痕中存在堆积。在所有样品中，处于高应力-应变状态的原子区集中在界面和压头周围，界面充当防止应力和应变扩散到基板内部的屏障。此外，由于基体与压头之间的摩擦，高温状态下的原子区集中在压头周围，材料从弹性到塑性的变形过程导致基体热量增加。