摘要
利用电弧复合磁控溅射技术制备不同Ti/Al比的Ti-Al-C涂层,结合后续的退火处理制备Ti_2AlC相涂层。利用SEM、EDS、XRD、Raman光谱仪和TEM等研究了Ti/Al比及退火温度对退火后Ti-Al-C涂层的相和微观结构的影响。结果表明,Ti-Al-C沉积态涂层为富Al层和TiCx层交替堆垛的多层结构,涂层表面大颗粒较少且结构致密。Ti/Al比对退火后涂层中的相结构有重要的影响:当Ti/Al比为2.04时,退火后涂层中Ti_2AlC的纯度和结晶度最高;Ti/Al比过高(3.06)时,退火后涂层中形成TiC和Ti_3AlC杂质相,而低Ti/Al比(0.54)则大幅度降低Ti_2AlC相的纯度和结晶度。同时,退火温度很大程度影响Ti_2AlC相的形成,当沉积态涂层中Ti/Al比为2.38时,Ti_2AlC相涂层形成的最佳退火温度为750℃,偏低的退火温度(600℃)下,原子不能充分扩散,难以形成211结构的Ti_2AlC相,而退火温度过高时(900℃)涂层中存在较多的TiC、TiAlx等杂质相。
Nuclear power generation provides a reliable and economic supply of electricity,due to low carbon emissions and relatively few waste.However,the reaction between zirconium and steam at high temperature is accompanied by the release of large amounts of hydrogen gas,which will bring serious consequences.After the Fukushima nuclear accident,the concept of accident-tolerant fuels(ATF)has been proposed and widely investigated.In terms of nuclear claddings,one key requirement is reduced oxidation kinetics with high-temperature steam and hence significantly reduced heat and hydrogen generation.An economical and simple method could be the preparation of protective coatings on the surface of zirconium alloys to improve the oxidation resistance.The MAX phase has been considered to be one of the most promising coating materials for nuclear cladding coatings.In this work,Ti-Al-C coatings with different Ti/Al ratios have been deposited on Zirlo alloy using a hybrid arc/magnetron sputtering method,and the Ti2AlC coatings were obtained by post-annealing.The effects of Ti/Al ratios and annealing temperatures on the phase and microstructure of Ti-Al-C coatings after annealing were studied by SEM,EDS,XRD,Raman spectrometer and TEM.It is found that Ti-Al-C coatings with different Ti/Al ratios deposited by the hybrid cathode arc/magnetron sputtering are a multi-layer structure of an alternative Al-rich layer and TiCxlayer.The as-deposited coatings are compact with a small amount of large particles.The Ti/Al ratio has an important influence on the phase structure of the annealed coating.When the Ti/Al ratio is 2.04,the highest purity and crystallinity of Ti2AlC are obtained.TiC and Ti3 AlC impurities will form within the coating at a higher Ti/Al ratio(3.06),while the purity and crystallinity of Ti2AlC will decrease at a lower Ti/Al ratio(0.54).In addition,the annealing temperature affects the formation of Ti2AlC to a great extent.When the Ti/Al ratio is 2.38,the optimum temperature for Ti-Al-C coatings to Ti2AlC coatings is at 750 ℃.The atom cannot diffuse fully at a lower annealing temperature(600 ℃),which is difficult to form the Ti2AlC phase,while a higher annealing temperature(900 ℃) will enable the formation of Ti2AlC coatings with more TiC,TiAlxand other impurities.
作者
李文涛
王振玉
张栋
潘建国
柯培玲
汪爱英
LI Wentao;WANG Zhenyu;ZHANG Dong;PAN Jianguo;KE Peiling;WANG Aiying(Faculty of Materials Science and Chemical Engineering,Ningbo University,Ningbo 315201,China;Key Laboratory of Marine Materials and Related Technologies,Ningbo Institute of Materials Technology and Engineering,Chinese Academy of Sciences,Ningbo 315201,China)
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
2019年第5期647-656,共10页
Acta Metallurgica Sinica
基金
国家重大科技专项项目No.2015ZX06004-001
中国博士后基金项目No.2018M632513
浙江省自然科学基金项目No.LQ19E01002
宁波市工业重点攻关项目No.2017B10042~~
