热腐蚀对GH4169高温合金δ相析出和拉伸性能的影响  

Influence of Hot Corrosion on Precipitation ofδPhase and Tensile Properties of GHGH4169 Superalloy

作　　者：宋肖肖 周律 李柯 任凯旭 王加余 王鑫 Song Xiaoxiao;Zhou Lv;Li Ke;Ren Kaixu;Wang Jiayu;Wang Xin(Sino-European Institute of Aviation Engineering,Civil Aviation University of China,Tianjin 300300,China;China Automotive Technology and Research Center Co.,Ltd,Tianjin 300300,China)

机构地区：[1]中国民航大学中欧航空工程师学院,天津300300 [2]中国汽车技术研究中心有限公司,天津300300

出　　处：《稀有金属材料与工程》2021年第10期3427-3436,共10页Rare Metal Materials and Engineering

基　　金：Fundamental Research Funds for the Central Universities of Civil Aviation Universities of China(3122019177)。

摘　　要：分别在650、750、850℃热处理条件下,研究了高温合金GH4169在75Na_(2)SO_(4)+25NaCl(质量分数)熔盐环境下的热腐蚀行为,之后进行组织表征和力学性能测试。结果表明:随着热处理温度的不断升高,高温合金的抗拉极限强度(UTS)和屈服强度(YS)都出现急剧退化,伸长率显著提高。但在750℃条件下,晶界处析出的针状δ相能提高高温合金的强度,导致合金出现沿晶脆性断裂现象,降低了合金的塑性。在650和750℃下,腐蚀机理符合Ⅱ型热腐蚀,但在850℃条件下符合Ⅰ型热腐蚀,2种不同类型腐蚀都促进了基体δ相的析出。The hot corrosion behavior of the superalloy GH4169 were analyzed in the salt mixture of 75Na_(2)SO_(4)+25NaCl(wt%)at 650,750 and 850℃ for 50,75 and 100 h.Then the precipitation ofδphase and tensile properties of the superalloy at ambient temperature were investigated.Results show that with increasing the heat treatment temperature,the ultimate tensile strength(UTS)and yield strength(YS)of the alloy exhibit a drastic degradation while elongation improves significantly.The needle-shapedδphase precipitated at the grain boundaries can enhance the strength of the superalloy,and cause intergranular brittle fracture.As a result,the ductility of the superalloy is reduced after exposure at 750℃.The corrosion mechanism of the alloy conforms to type-II hot corrosion at 650 and 750℃ while to type-I hot corrosion at 850℃.Both kinds of corrosion can form a corrosion layer and promote theδphase precipitation.

关 键 词：热腐蚀 GH4169高温合金 Δ相 拉伸性能 

分 类 号：TG132.3[一般工业技术—材料科学与工程]