Nanostructured crystalline Al/amorphous AlN multilayer films, with a wide layer thickness (h) range from 10 to 200 nm, were prepared and exposed to high-temperature annealing from 200 to 600 °C. Microstructure of all the multilayers was highly stable under the temperature up to 400 °C. Apparent grain coarsening happened in multilayers with h > ~50 nm under 500 °C. However, the Al grains in h ≤ ~50 nm multilayers were extremely stabilized under even 500 °C annealing, showing a high thermal resistance up to about 0.8T_m (T_m: melting point of bulk pure Al). The stabilization mechanisms mainly include the constraint effect by heterophase interface and the nanotwinning in Al layers, as demonstrated by statistical measurement results and ex-situ/in-situ transmission electron microscope observations. When the annealing temperature was raised up to 600 °C, the heterophase interfaces disappeared in h ≤ ~20 nm samples but were well preserved when h > ~20 nm, revealing that the thermal failure modes were quite sensitive to h. Based on the microstructural evolution, a thermal failure map was finally developed in variation with h and annealing temperature. Furthermore, hardness of the multilayers was measured and hardening mechanism was also discussed according to the microstructural evolution after annealing.

制备了具有10至200 nm的较宽层厚度（h）的纳米结构晶体Al /非晶AlN多层膜，并使其经受了200至600°C的高温退火。在高达400°C的温度下，所有多层的微观结构都高度稳定。在500°C下h>〜50 nm的多层膜中出现了明显的晶粒粗化。然而，在所述Al晶粒ħ ≤〜50nm的多层膜进行了极其甚至500℃下退火稳定，表现出高的耐热性高达约0.8 Ť_米（Ť_米：大块纯Al的熔点）。统计测量结果和非原位/原位透射电子显微镜观察表明，稳定机制主要包括异相界面的约束效应和铝层中的纳米孪晶。当退火温度升高至600℃时，多相接口中消失ħ ≤〜20nm的样品但被完好地保存当ħ >〜20纳米，揭示了热故障模式是到相当敏感ħ。基于微观结构的演变，最终得出了随h变化的热破坏图。和退火温度。此外，根据退火后的显微组织演变，测量了多层的硬度并讨论了硬化机理。