相图计算辅助新型Co基变形高温合金的成分设计  

Composition Design for Novel Co-Al-W-Based Wrought Superalloy Aided by CALPHAD Approach

作　　者：吴刚 王涛 沈剑韵 魏杰[1,2,3] 吴波 黄永章[1,2,3] 袁学韬 Wu Gang;Wang Tao;Shen Jianyun;Wei Jie;Wu Bo;Huang Yongzhang;Yuan Xuetao(National Engineering Laboratory of Biohydrometallurgy,GRINM Engineering Institute Co.,Ltd,Beijing 101407,China;China GRINM Resources and Environment Tech.Co.,Ltd,Beijing 101407,China;General Research Institute for Nonferrous Metals,Beijing 100088,China;Science and Technology on Advanced High Temperature Structural Materials Laboratory,AECC Beijing Institute of Aeronautical Materials,Beijing 100095,China;College of Materials Science and Engineering,Fuzhou University,Fuzhou 350108,China)

机构地区：[1]有研科技集团有限公司生物冶金国家工程实验室,北京101407 [2]有研资源环境技术研究院(北京)有限公司,北京101407 [3]北京有色金属研究总院,北京100088 [4]中国航发北京航空材料研究院先进高温结构材料重点实验室,北京100095 [5]福州大学材料科学与工程学院,福建福州350108

出　　处：《稀有金属材料与工程》2021年第1期235-241,共7页Rare Metal Materials and Engineering

摘　　要：为了确定Co-Al-W-Ni-Ta-Ti体系新型γ′强化的Co-Al-W基变形高温合金的成分及相应的热处理工艺,利用Pandat计算软件及钴基高温合金热力学数据库,计算了合金元素对平衡相析出行为的影响。计算表明:W、Ni、Ta及Ti均能提高γ′的稳定性,W、Ta会增加有害相χ-D019的析出倾向,Ti和Ni能分别抑制有害相χ-D019和B2相的析出,将合金成分定为Co-9Al-3W-30Ni-2Ta-3.5Ti(at%)。计算了此合金的相转变规律,结果表明:合金的平衡析出相为γ、γ′、χ-D019和Co7Ta2,开始析出温度分别为1355,1169,700和288℃。制定了合金的热处理制度:1250℃/12 h均匀化,1150℃/6 h固溶处理,900℃/4 h+750℃/16 h两步时效处理。采用真空感应熔炼制备了合金样品,经上述热处理后,DSC分析结果与计算的相转变规律一致,SEM及XRD结果表明,合金中的平衡相为典型的γ+γ′两相组织。In order to determine the composition of the novelγ′strengthened Co-Al-W-based wrought superalloy of the Co-Al-W-Ni-Ta-Ti system and the corresponding heat treatment process,using Pandat calculation software and the thermodynamic database of cobalt-based superalloys,the influence of alloying elements on the precipitation behavior of the equilibrium phase was calculated.The results show that W,Ni,Ta,and Ti can improve the stability ofγ′,W,Ta can increase the precipitation tendency of the harmful phaseχ-D019,and Ti and Ni can suppress the precipitation of the harmfulχ-D019 phase and B2 phase,respectively.So the alloy composition is determined as Co-9Al-3W-30Ni-2Ta-3.5Ti(at%).The phase transition law of this alloy was calculated,and the results showed that the equilibrium precipitation phases of the alloy wereγ,γ′,χ-D019 and Co7Ta2,and the initial precipitation temperatures were 1355,1169,700,and 288℃,respectively.The alloy heat treatment process is determined:1250℃/12 h homogenization,1150℃/6 h solution treatment,and 900℃/4 h+750℃/16 h two-step aging treatment.The alloy samples were prepared by vacuum induction melting.After the above heat treatment,the DSC analysis results show consistency with the calculated phase transition rules.SEM and XRD results show that the equilibrium phase of the alloy is typicalγ+γ′two-phase structure.

关 键 词：Co-Al-W基变形高温合金 相图计算(CALPHAD) 成分设计 

分 类 号：TG146.16[金属学及工艺—金属材料] TG132.33[金属学及工艺—金属学]