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用磁控溅射技术获得了晶粒尺寸小于１００ｎｍ的Ｃｏ—３０Ｃｒ—５Ａｌ微晶涂层。对同成分ＣｏＣｒＡｌ合金及其微晶涂层进行１１００℃恒温和１０００℃循环氧化试验，并与ＣｏＣｒＡｌＹ合金进行比较。用声发射技术、划痕法及透射电镜对溅射ＣｏＣｒＡｌ微晶涂层的抗氧化机理进行了研究。结果表明微晶化提高了ＣｏＣｒＡｌ合金表面氧化膜的粘附性，从而大大改善了合金的抗恒温与循环氧化性能。而微晶化提高氧化膜粘附性的原因是：（１）微晶表面氧化膜比铸态合金表面氧化膜的晶粒细得多，细晶氧化膜可通过扩散蠕变释放生长应力和部分热应力；（２）微晶涂层氧化膜的热应力可通过靠近氧化膜的微晶合金的塑性变形而释放；（３）溅射微晶涂层具有柱状结构，沿柱状结构氧化可产生许多“微钉”，从而大大提高了氧化膜的附着力。从氧化膜的附着力和塑性看，微晶化比添加活性元素的作用还大。
The Co-30Cr-5Al microcrystalline coating with grain size less than 100nm was obtained by magnetron sputtering. The same composition of CoCrAl alloy and its microcrystalline coating 1100 ℃ constant temperature and 1000 ℃ cyclic oxidation test, and compared with the CoCrAlY alloy. The anti-oxidation mechanism of the sputtered CoCrAl microcrystalline coating was studied by acoustic emission technique, scratch method and transmission electron microscopy. The results show that microcrystallization improves the adhesion of the oxide film on the surface of CoCrAl alloy, which greatly improves the anti-thermostatic and cyclic oxidation properties of the alloy. The reasons for the microcrystallization to improve the adhesion of the oxide film are as follows: (1) the microcrystalline surface oxide film is much thinner than the oxide film on the as-cast alloy surface, the fine crystalline oxide film can release the growth stress and part by diffusion creep Thermal stress; (2) the thermal stress of the microcrystalline coating oxide film can be released by the plastic deformation of the microcrystalline alloy close to the oxide film; (3) the sputtered microcrystalline coating has a columnar structure and oxidation along the columnar structure can produce many “Micro-nails”, thus greatly improving the adhesion of the oxide film. Judging from the adhesion and plasticity of the oxide film, the effect of the microcrystallization is greater than that of adding the active element.