包埋渗铝获得的镍铝涂层是一种最早使用的Al2O3膜热生长型高温涂层.自20世纪50年代应用于航空发动机热端部构件的高温防护以来,进一步提高其抗高温氧化性能的机理和技术研究延续至今.基于对合金氧化及Al2O3膜热生长机制的理解,提出了晶粒细化与特定金属氧化物掺杂可提升镍铝涂层抗氧化性能的观点,介绍了涂层晶粒细化与金属氧化物弥撒掺杂方法,讨论了这些结构和成分改性影响涂层抗高温氧化性能的关键因素:包括Al2O3膜生长速度、亚稳态相向稳态相转变、涂层的黏附性以及涂层与合金基体的互扩散.这些新的研究结果有望为进一步挖掘渗铝涂层的应用潜力、延长其服役寿命提供理论和试验基础.%NiAl coating obtained by pack aluminization is the firstly used as Al2O3-forming high-temperature coating. Since the middle of the last century, NiAl coatings were employed in hot sections of aero-engines for protection against high temperature oxidation. Investigations of the oxidation mechanisms of the coating, and exploration of the coating techniques continue up to now. On a basis of understanding to the oxidation mechanism of alloys and thermal growth of Al2O3, a concept of improving the oxidation resistance of nickel aluminide coating by means of grain refinement and typical metal oxide dispersions has been proposed. Meanwhile a method to refine the grains of the nickel aluminide coating and disperse it with metal oxide nanoparticles has been presented, and key factors (including growth rate of the Al2O3 scale, Al2O3 phase transformation from metastable phases to the stable phase, the Al2O3 adhesion to the coating as well as the interdiffusion between the coating and the metal substrate) intrinsically correlated with the oxidation resistance of the coating which can be significantly affected by its modification in microstructure and chemical composition have been reviewed. The new result is expected to be helpful to further offer theoretical and experimental bases for tapping the potential and prolonging the service life of the aluminized coatings in application.
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