摘要
Ni-Fe-Cr基合金是在GH925合金基础上,通过增Ni、Al降Cr、Ti获得的一种改进型沉淀硬化型高温合金。采用差热扫描量热/热重法(DSC/TG)、SEM/EDS、XRD等方法分析测定了Ni-Fe-Cr合金在800、900、1000℃恒温下空气中的氧化动力学。研究发现,合金在800和900℃时,氧化初期呈波动性变化,这与该温度下强化相γ″-Ni3Nb转变为板条状δ-Ni3Nb组织有关,氧化膜稳定后,氧化增重遵循线性增长。在1000℃时,合金氧化动力学符合抛物线规律,但初始氧化速率更大,氧化膜有开裂现象。不同温度下表层氧化物主要由Cr2O3、Fe2O3、NiO、TiO2以及尖晶石结构的NiCr2O4和CrTiO3组成,内层氧化物主要是Al2O3和TiO2。
Based on Incoloy 925 alloy,Ni-Fe-Cr based alloy is a new type of precipitation hardening superalloy,which is obtained by increasing the contents of Ni,Al and decreasing the contents of Cr and Ti.It is widely used in aerospace and sulfur-containing oil and gas engineering.The oxidation kinetics of Ni-Fe-Cr alloy in air at 800℃,900℃and 1000℃was studied by the methods of DSC/TG,SEM/EDS and XRD.It is found that the initial oxidation stage of the alloy changed with fluctuation at 800℃and 900℃,which may be related to the transformation of the precipitated phaseγ″-Ni3Nb and plant-likeδ-Ni3Nb at these temperature zones.With the stable oxidation film formed,the oxidation mass gain ratio to the time followed a linear growth.When the temperature was 1000℃,the oxidation kinetics accorded with the parabolic law,but the initial oxidation rate was higher than the low ones and the oxide film cracked.The surface oxide was mainly composed of Cr2O3,Fe2O3,NiO,TiO2 and spinel structure of NiCr2O4 and CrTiO3,while the inner oxide was mainly Al2O3 and TiO2.
作者
张玉碧
李振军
杨晓亮
张红松
ZHANG Yubi;LI Zhenjun;YANG Xiaoliang;ZHANG Hongsong(Mechanical College of Engineering,Henan Institute of Engineering, Zhengzhou 451191,China;Chongqing Materials Research Institute Co., Ltd.,Chongqing 400707,China)
出处
《功能材料》
EI
CAS
CSCD
北大核心
2020年第11期11159-11164,共6页
Journal of Functional Materials
基金
河南省自然科学基金资助项目(182300410253)
河南省科技开放合作资助项目(172106000060)
河南省高校科技创新团队支持计划资助项目(18IRTSTHN005)。
