摘要
以内送粉和外送粉两种方式微弧等离子喷涂工艺制备了NiCrAlY/Al_2O_3复合涂层,分析了送粉方式对涂层相组成、微观结构和介电性能的影响。结果表明:与外送粉相比,内送粉方式沉积的涂层具有较高的沉积效率和较低的孔隙率。由于喷涂过程中α-Al_2O_3颗粒完全熔融,内送粉喷涂所得到涂层主要为γ/γ′和γ-Al_2O_3相,并且涂层结构致密,NiCrAlY颗粒分布均匀。介电性能测试表明,以外送粉方式制备的涂层复介电常数实部和虚部几乎不随频率发生变化。而以内送粉方式喷涂的涂层复介电常数实部和虚部随频率的增加而降低,呈现明显的频散现象。
NiCrAlY/Al2O3 composite coatings were fabricated by micro-arc plasma spraying technology with internal and external feedstock injection methods. The effect of powder infection method on the phase composition, microstrueture and dielectric properties was analyzed. Results show that： compared with the coatings prepared with external feedstock injection method, the deposition efficiency of the coatings with internal feedstock method is higher and the porosity of that is lower. Because of the completely melted α-Al2O3 particles, the coatings prepared with internal feedstock injection method are mainly composed of γ/γ＇ and γ-Al2O3, and their microstructure is dense, the distri- bution of NiCrAIY particles is uniform. The measurements of dielectric properties revealed that the real and imaginary parts of the coatings with external feedstock injection method almost do not vary with frequency. However, the real and imaginary parts of the coatings with internal feedstock injection method decrease with the increase of frequency, which represents obviously frequency dispersion phenomenon.
出处
《宇航材料工艺》
CAS
CSCD
北大核心
2015年第3期59-62,共4页
Aerospace Materials & Technology
基金
国家自然科学基金资助项目(51302018)
陕西省自然科学基础研究计划资助项目(2014JQ6210)
西北工业大学凝固技术国家重点实验室开放课题资助项目(SKLSP201319)
关键词
送粉方式
等离子喷涂
金属陶瓷
介电性能
Powder injection method, Plasma spraying, Cermets, Dielectric properties
