包壳用锆合金表面Cr涂层的高温耐蚀性能  

High Temperature Corrosion Resistance of Cr Coating on Surface of Zirconium Alloy Cladding

作　　者：王毅飞[1,2] 刘春明 王彦峰 耿娟娟[1] Wang Yifei;Liu Chunming;Wang Yanfeng;Geng Juanjuan(Institute of Corrosion and Protection,Northwest Institute for Nonferrous Metal Research,Xi'an 710016,China;School of Materials Science and Engineering,Northeastern University,Shenyang 110819,China)

机构地区：[1]西北有色金属研究院腐蚀与防护研究所,陕西西安710016 [2]东北大学材料科学与工程学院,辽宁沈阳110819

出　　处：《稀有金属》2022年第8期1013-1020,共8页Chinese Journal of Rare Metals

基　　金：陕西省自然科学基金项目(2020JM-649);陕西省重点研发计划项目(2020GY-283);陕西省科技重大专项项目(2020zdzx04-03-02)资助。

摘　　要：为了提高包壳用锆合金的耐高温腐蚀性能,采用等离子增强物理气相复合沉积(PPC)技术在Zr-4合金试样表面制备了厚度为15μm的Cr涂层,并对其性能进行了表征。通过在(420±3)℃,(10.3±0.7)MPa高温高压蒸汽中进行100 d腐蚀试验,对比了Zr-4基体和Cr涂层试样在高温蒸汽中腐蚀100 d后的耐蚀性能,利用X射线衍射(XRD)分析了涂层的物相,利用扫描电镜(SEM)分析了试样腐蚀后的氧化层厚度及断面形貌,利用能谱(EDS)线扫描分析了腐蚀后试样断面的元素成分,利用金相显微镜(OM)检测试样内部氢化物分布并采用气体分析法测量氢含量。结果表明:采用PPC技术制备的Cr涂层均匀致密,无裂纹、孔洞等缺陷;经高温高压蒸汽腐蚀后,试样表面Cr涂层氧化加重,随着腐蚀时间的延长,基体表面氧化膜厚度逐渐增加,而Cr涂层会发生减薄现象,但剩余涂层连续致密,且基体未出现氧化腐蚀现象,说明Cr涂层具有良好的耐蚀性能;涂层试样比基体具有更低的腐蚀增重率,说明Cr涂层能对基体起到保护作用;Cr涂层部分涂覆的试样涂层与基体过渡区基体侧出现氧化层,但氧化层厚度均匀一致,说明Cr涂层并未加速基体的腐蚀;与Zr-4基体试样相比,Cr涂层明显阻碍了基体的吸氢,减少了氢化物的析出。In this work,the effect of Cr coating on improving the high temperature corrosion resistance of zirconium alloy cladding surface was investigated.The corrosion resistance of Zr-4 alloy and Zr-4 alloy protected by Cr coating of 15μm thickness(Zr-4/Cr)that was introduced via plasma enhanced physical vapor composite deposition technology(PPC)were subjected to high temperature steam corrosion in(420±3)℃and(10.3±0.7)MPa for 100 d.The samples were analyzed via X-ray diffraction(XRD),scanning electron macrocsope(SEM),energy dispersive spectroscopy(EDS)and metallographic microscope inspection test for the elemental composition of the coating,oxide layer thickness and section morphology,element composition of section,hydrogen content and hydride distribution,respectively.The analyses suggest the following observations:PPC prepared Cr coatings was uniform and dense,without defects such as cracks and holes,and the film-substrate interface was continuous and complete without defects.XRD pattern of the coating showed two main peaks of Cr(110)and Cr(200),and the typical microstructure of the coating exhibited a Cr(200)preferred orientation.After being corroded by high temperature and high-pressure steam,Cr coating became more oxidized.As the corrosion time increased,the diffusion depth of oxygen in the substrate,increased.With different corrosion times,oxide films with thicknesses of about 4,6,8 and 9μm were formed on the surface of the substrate,respectively,and the oxide film was relatively dense,and the interface between the coating and the substrate was closely bonded after corrosion,and there was no interface crack or peeling phenomenon.After 25 d of corrosion,the remaining thickness of the coating was about 14μm,and after 50 d of corrosion,the remaining thickness of the coating was about 12 and 10μm,respectively.Especially after 100 d of corrosion,the remaining thickness of the coating was about 8μm.After corrosion,the content of O element in the coating was higher than that in the substrate,and O content in the

关 键 词：锆合金 包壳材料 Cr涂层 高温耐蚀 

分 类 号：TG174.44[金属学及工艺—金属表面处理]