稀土Y,Ce对K418镍基高温合金微观组织的影响  

Effect of Rare Earth Elements(Y,Ce)on Microstructure of K418 Ni-base Superalloy

作　　者：金玉花[1] 韩萍花 李常锋[1] 寇生中[1] 

机构地区：[1]兰州理工大学甘肃省有色金属新材料省部共建国家重点实验室,兰州730050

出　　处：《材料工程》2016年第3期46-51,共6页Journal of Materials Engineering

基　　金：973计划前期研究专项基金(2012CB722806);兰州理工大学2013年博士基金(01-0765);甘肃省高等学校基本科研业务费(01-0071)

摘　　要：采用高真空电弧熔炼炉熔炼,制备了K418镍基高温合金。借助SEM对合金的组织进行观察,用EDS对合金中的相成分进行分析,研究了稀土元素Y,Ce对合金中气孔缺陷、γ′相以及(γ+γ′)共晶相等的影响。结果表明:添加稀土元素明显减少了合金中的气孔缺陷,提高了合金的致密度,细化了合金枝晶组织。组织中碳化物的形态由大块状变为链状和小块状,γ′相尺寸变小且颗粒数目增多。Y元素的加入能使合金中的(γ+γ′)共晶相数目增加。但同时加入Y,Ce两种稀土元素后共晶相数目的增加更为显著。K418Ni-base superalloy was melted in high vacuum arc-melting furnace.The microstructure was observed by using SEM,the phase composition was detected by EDS.The effect of with rare earth elements on pore defects,γ′phase and eutectic phase of the alloy was studied and the effect mechanism was analyzed.The results show that the pore defects of the alloy decrease with the addition of rare earth elements,the density increases,the dendritic structure is refined.The morphology of carbides in alloy turns from bulk into chain and small pieces,theγ′phase in alloy with the addition of rare earth elements becomes smaller in size and much more in numbers.The eutectic phase（γ＋γ′）volume remarkably increases with the addition of Y,however the eutectic phase volume increases more obviously if two rare earth elements Y,Ce are added simultaneously.

关 键 词：K418合金 稀土元素 γ′相 共晶相 

分 类 号：TG146.15[一般工业技术—材料科学与工程]