Mayrhofer P H, Sonnleitner D, Bartosik M, Holec D
Institute of Materials Science and Technology, Vienna University of Technology, A-1040 Vienna, Austria.
Department of Physical Metallurgy and Materials Testing, Montanuniversität Leoben, A-8700 Leoben, Austria.
Surf Coat Technol. 2014 Apr 15;244(100):52-56. doi: 10.1016/j.surfcoat.2014.01.049.
The influence of reactive and non-reactive sputtering on structure, mechanical properties, and thermal stability of ZrAlN thin films during annealing to 1500 °C is investigated in detail. Reactive sputtering of a ZrAl target leads to the formation of ZrAlN thin films, mainly composed of supersaturated cubic (c) ZrAlN with small fractions of (semi-)coherent wurtzite (w) AlN domains. Upon annealing, the formation of cubic Zr-rich domains and growth of the (semi-)coherent w-AlN domains indicate spinodal-like decomposition. Loss of coherency can only be observed for annealing temperatures above 1150 °C. Following these decomposition processes, the hardness remains at the as-deposited value of ~ 29 GPa with annealing up to 1100 °C. Using a ceramic (ZrN)(AlN) target and sputtering in Ar atmosphere allows preparing c-ZrAlN coatings with a well-defined crystalline single-phase cubic structure combined with higher hardnesses of ~ 31 GPa. Due to the absence of (semi-)coherent w-AlN domains in the as-deposited state, which could act as nucleation sites, the decomposition process of c-ZrAlN is retarded. Only after annealing at 1270 °C, the formation of incoherent w-AlN can be detected. Hence, their hardness remains very high with ~ 33 GPa even after annealing at 1200 °C. The study highlights the importance of controlling the deposition process to prepare well-defined coatings with high mechanical properties and thermal stability.
详细研究了反应溅射和非反应溅射对ZrAlN薄膜在退火至1500°C过程中的结构、力学性能和热稳定性的影响。ZrAl靶的反应溅射导致ZrAlN薄膜的形成，主要由过饱和立方（c）ZrAlN组成，并含有少量（半）相干纤锌矿（w）AlN畴。退火时，立方富Zr畴的形成和（半）相干w-AlN畴的生长表明发生了类旋节分解。仅在退火温度高于1150°C时才能观察到相干性的丧失。在这些分解过程之后，在退火至1100°C时，硬度保持在沉积态时的约29 GPa。使用陶瓷（ZrN）（AlN）靶并在Ar气氛中溅射，可以制备具有明确结晶单相立方结构且硬度更高（约31 GPa）的c-ZrAlN涂层。由于在沉积态不存在可作为成核位点的（半）相干w-AlN畴，c-ZrAlN的分解过程受到阻碍。仅在1270°C退火后，才能检测到非相干w-AlN的形成。因此，即使在1200°C退火后，它们的硬度仍保持在非常高的约33 GPa。该研究强调了控制沉积过程以制备具有高力学性能和热稳定性的明确涂层的重要性。
