摘要
功能梯度阴极基于表面强化层实现耐烧蚀性能和传导性能的解耦,能够有效延长阴极服役寿命。本研究围绕Nb/Cu功能梯度阴极,采取激光增材于Cu基体表面制备出Nb覆层,表征了Nb/Cu梯度阴极的微观组织、成分和物相结构,分析了硬度和热导率自覆层表面向内的变化规律。进一步地,对Nb/Cu功能梯度阴极的氩气氛围电弧放电和烧蚀行为进行了研究,高速滤光捕捉下,阴极放电表面出现多个阴极斑点团簇,烧损面形成密集烧蚀坑和溅射颗粒。Nb/Cu阴极氩气电弧烧蚀速率(1.61μg/C)相比无氧Cu阴极(2.18μg/C)降低26.1%,更耐电弧烧蚀。功能梯度阴极具备的优异耐电弧烧蚀性能,与Nb表层耐烧蚀性和Cu基体高传导性密切相关。Nb/Cu功能梯度阴极具备作为新型阴极应用的潜能。
Functionally gradient cathodes(FGC)realize the combination of ablation-resistant surface and conductive matrix,which can effectively extend the cathodic service life.Nb/Cu FGC,with Nb layer and Cu as surface and matrix,respectively,was prepared by laser cladding.The microstructure,composition,and the phase information were characterized.The microhardness and thermal conductivity of the FGC were tested.Furthermore,the cathodic discharge and ablation behavior in Ar atmosphere were investigated.Results show that several scattered cathode spots appear and densely distributed ablation craters are observed.The Nb/Cu FGC displays relatively moderate ablation behaviors.The average ablation rate of Nb/Cu FGC(1.61μg/C)is 26.1%lower than that of Cu cathodes(2.18μg/C),as ascribed to the synergy of ablation resistant Nb surface and the highly-conductive Cu matrix.Nb/Cu FGC exhibits the potential in arc plasma applications.
作者
关慰勉
刘玲玲
赵梁
梁新增
关峰
金银玲
贾大炜
刘嘉斌
Guan Weimian;Liu Lingling;Zhao Liang;Liang Xinzeng;Guan Feng;Jin Yinling;Jia Dawei;Liu Jiabin(Shenyang Aircraft Industry(Group)Co.,Ltd,Shenyang 110850,China;School of Materials Science and Engineering,Zhejiang University,Hangzhou 310058,China)
出处
《稀有金属材料与工程》
北大核心
2025年第6期1535-1542,共8页
Rare Metal Materials and Engineering
基金
国家自然科学基金重大研究计划重点项目(92266202)。
关键词
电弧放电
激光熔覆
功能梯度阴极
铌覆层
烧蚀
arc discharge
laser cladding
functionally gradient cathodes
Nb layer
ablation
