纳米CeO_(2p)对镍基高温合金表面NiCoCrAlY激光熔覆涂层氧化行为的影响  

EFFECTS OF NANO-CeO_(2p) ON OXIDATION BEHAVIORS OF NiCoCrAlY LASER CLADDING COATINGS ON Ni-BASED SUPERALLOYS

作　　者：王宏宇[1,2] 左敦稳[1] 王明娣[3] 邵建兵[1] 

机构地区：[1]南京航空航天大学江苏省精密与微细制造技术重点实验室,南京210016 [2]江苏大学机械工程学院,镇江212013 [3]苏州大学机电学院,苏州215021

出　　处：《金属学报》2009年第8期971-977,共7页Acta Metallurgica Sinica

基　　金：高等学校博士学科点专项科研基金项目20060287019;江苏省材料摩擦学重点实验室开放基金项目kjsmcx07001;江苏省研究生科研创新计划项目CX08B-39Z资助~~

摘　　要：纳米CeO_(2p)是合金中最为常用的一种稀土改性材料,可明显改善合金的抗氧化性能.为了研究纳米CeO_(2p)对双层热障涂层中NiCoCrAlY粘结层抗氧化性能的影响.本文采用激光熔覆技术,在镍基高温合金表面上制备了4种纳米CeO_(2p)含量不同的NiCoCrAlY粘结涂层,分析了它们在1050℃空气氛围中的等温氧化行为,并初步探讨了纳米CeO_(2p)的作用机制.结果表明:添加纳米CeO_(2p)的涂层的抗氧化性能均高于未加纳米颗粒的涂层,其中添加2%(质量分数)纳米CeO_(2p)的涂层抗氧化性能最好.在氧化100 h后,添加2%纳米CeO_(2p)涂层的质量增加仅为1.56 mg/cm^2,较未加纳米颗粒的涂层减少一半以上;同时,涂层进入稳态氧化所需要的时间极短.仅为未加纳米颗粒的涂层的1/20;此外,涂层氧化膜在长时间氧化后仍很致密,涂层内部仅出现轻微的内氧化,而相同氧化条件下的未加纳米颗粒的涂层的氧化膜已趋于失效.Nano-CeO2p, which is most commonly used as a kind of rare earth modified material of alloys, possesses a prominent advantage in improving oxidation resistance. To study how nano CeO2p will affect the oxidation resistance of NiCoCrAIY bondcoat in double-layer thermal barrier coatings, in this work, four kinds of the NiCoCrA1Y coatings with different contents of nano CeO2p were prepared on the surface of a Ni based superalloy using laser cladding technology, their isothermal oxidation behaviors in atmosphere under 1050 ℃ were investigated, and the influence mechanism of nano-CeO2p on the oxidation resistance of coatings was preliminary discussed. The results show that all these coatings with nano-CeO2p have better oxidation resistance than those without nano-CeO2p, among which the coating with 2% （mass fraction） nano-CeO2p, has the best oxidation resistance. After 100 hours of oxidation, its oxidation mass gain is only 1.56 mg/cm2, reducing by more than half compared with the coatings without nano CeO2p; meanwhile, it takes extremely short time to enter the steady oxidation stage, only about 1/20 of the coating without nano CeO2p. Besides, the oxide layer of the coating is still very dense even after a long time oxidation and only a slight internal oxidation takes place within the coating, however, in that case, the oxide layer of the coatings without nano-CeO2p is out of operation.

关 键 词：NICOCRALY涂层 等温氧化 纳米CeO2p 影响机制 激光熔覆 镍基高温合金 

分 类 号：TG174.4[金属学及工艺—金属表面处理] TF125.5[金属学及工艺—金属学]