纳米NiCrBSi-TiB_2涂层800℃循环氧化行为研究  

Cycle Oxidation Behavior of Nanostructured NiCrBSi-Ti B_2 Coating at 800 ℃

作　　者：吴姚莎[1] 王迪[2] 李尚周[2] 洪方[2] 

机构地区：[1]中山火炬职业技术学院光电工程系,广东中山528436 [2]华南理工大学机械与汽车学院,广东广州510640

出　　处：《热加工工艺》2015年第8期143-147,共5页Hot Working Technology

基　　金：广东省自然科学基金资助项目(S201304001636);中山市科技计划项目(20123A380)

摘　　要：采用超音速火焰喷涂技术制备纳米Ni Cr BSi-Ti B_2涂层,对比研究了纳米和微米涂层在800℃下的循环氧化行为。结果表明:纳米涂层表面由完整连续的外层Si O_2膜+内层Cr_2O_3膜构成,细小的Ti O_2颗粒弥散地分布于Si O_2膜上。在800℃循环氧化条件下,纳米涂层氧化增重曲线遵循抛物线规律,扩散机制为该涂层氧化过程中的主要控制步骤。在氧化过程中,纳米涂层表面形成了完整连续的外层Si O_2膜+内层Cr_2O_3膜,同时晶粒细化能够降低涂层内应力,有效地防止涂层开裂,提高了涂层的抗氧化性能。Cycle oxidation resistance at 800 ℃was investigated for a nanostmctured NiCrBSi-TiB2 coating sprayed by high velocity oxy-fuel. For comparison, the conventional NiCrBSi-TiB2 coating was also studied. The results indicate that the structure of oxide scale from external to internal on the nanostmctured coating is complete and continuous SiO2 scale→Cr2O3 scale, and the loose TiO2 particles diffuse on the oxide films. The oxidation process of the nanostmctured coating is controlled by a diffusion mechanism, and the nanostmcmred coating exhibits better cycle oxidation resistance than that of the conventional coating. The reasons for improved oxidation resistance of the nanostructured coating can be attributed to the fact of the formation of the continuous-compact protective SiO2＋Cr2O3 scale and the significant enhancement adhesion between oxide scale and coating.

关 键 词：表面科学 纳米涂层 循环氧化 TI B2 

分 类 号：TG174.4[金属学及工艺—金属表面处理]