NiCrAlY涂层与Ni3Al基单晶高温合金IC21基体互扩散行为研究  

Interdiffusion behaviour of NiCrAlY coating and IC21single crystal superalloy

作　　者：曹家旭 邓鹏 邓春明 杨焜 李风[1] CAO Jiaxu;DENG Peng;DENG Chunming;YANG Kun;LI Feng(School of Materials and Energy,Guangdong University of Technology,Guangzhou 510006,China;Guangdong Institute of New Materials,National Engineering Laboratory for Modern Materials Surface Engineering Technology,The Key Lab of Guangdong for Modern Surface Engineering Technology,Guangzhou 510650,China)

机构地区：[1]广东工业大学材料与能源学院,广东广州510006 [2]广东省新材料研究所,现代材料表面工程技术国家工程实验室,广东省现代表面工程技术重点实验室,广东广州510650

出　　处：《材料研究与应用》2020年第2期87-94,共8页Materials Research and Application

基　　金：广东省科技计划项目(No.2019B010936001,No.2017A070701027);广东省科学院项目(No.2018GDASCX-0402)

摘　　要：采用低压等离子喷涂技术在Ni3Al基单晶高温合金IC21基体上沉积NiCrAlY涂层.将样品在1150℃的恒定温度下进行200h的静态氧化,利用SEM、EDS、XRD及TEM表征涂层和基体在高温下互扩散后的微观结构和相组成,得到涂层与基体高温下的互扩散规律.结果表明:NiCrAlY涂层/IC21单晶在1150℃下静态氧化5h时出现了互扩散区(IDZ)和二次反应区(SRZ);随着氧化时间的延长,IDZ的厚度呈现逐渐增宽趋势,初始0~50h时IDZ厚度增率攀升较快,50~100h时增长有放缓趋势,100~200h时增速下降明显;NiCrAlY涂层/IC21单晶在1150℃下静态氧化后产生了两种不同取向的析出相,分别为针叶状和竹叶状,析出相成分均包含Re,Mo,Cr及Ni元素且成分相近,根据晶面间距计算得出该相为μ-TCP相,出现不同取向的原因为Re和Mo元素易在基体中形成局部过饱和,元素的差异使μ-TCP相优先沿着Re或者Mo含量较高的晶面生长,从而使μ相产生两种不同取向.NiCrAlY is deposited on Ni3Al-based IC21single crystal superalloy by low-pressure plasma spraying technology.The coated samples were subjected to static oxidation for 200hat a constant temperature of 1150℃.SEM,EDS,XRD and TEM were used to characterize the microstructure and phase composition of the coating and substrate after interdiffusion at high temperature.The results show that the inter-diffusion zone(IDZ)and the secondary reaction zone(SRZ)appear when the NiCrAlY coated IC21single crystal superalloy was oxidized at 1150℃for 5h.With the extension of the oxidation time,the thickness of IDZ was gradually widened.However,the growth rate of IDZ thickness was increased at the initial of 0-50h,then the growth rate was slowed down at 50-100h,and the growth rate was decreased significantly in the final of 100-200h.NiCrAlY coating/IC21single crystal statically oxidized at 1150℃produced two different orientations of the precipitated phases were needle-shaped and bamboo leaf-shaped.The components of the precipitated phase included Re,Mo,Cr,Ni and the components were similar.According to the calculation results of the interplanar distance,this phase wasμ-TCP phase.The reason for the different orientations is that Re and Mo are easy to be locally supersaturated in the substrate.The difference in elements made theμ-TCP phase preferentially grows along the crystal plane with a higher Re or Mo content,so that theμ-TCP phase produced two different orientations.

关 键 词：Ni3Al基单晶高温合金IC21 NICRALY涂层 静态氧化 互扩散 

分 类 号：TG174.44[金属学及工艺—金属表面处理]