以Mo代W对单晶高温合金组织、凝固特性与错配度影响的热力学研究  

Thermodynamic Investigation of Influence of Substituting Mo for W on Microstructure, Solidification Characteristics and Lattice Misfit of Single Crystal Superalloy

作　　者：艾诚 孙阳辉 刘林[2] AI Cheng;SUN Yanghui;LIU lin(School of Material Science and Engineering, Chang＇an University, Xi＇an 710064,China;State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi＇an 710072, China)

机构地区：[1]长安大学材料科学与工程学院,陕西西安710064 [2]西北工业大学凝固技术国家重点实验室,陕西西安710072

出　　处：《热加工工艺》2018年第8期74-77,86,共5页Hot Working Technology

基　　金：国家自然科学基金项目(51701020,51331005,51631008);国家重点研发计划项目(2017YFB0702902);中国博士后科学基金项目(2016M602735);中央高校基本科研业务费专项资金资助项目(310831171004)

摘　　要：基于d电子原理,设计了高W强化Ni基单晶高温合金Alloy W和高Alloy Mo强化Ni基单晶高温合金Mo。热力学计算的结果表明,以Mo代W降低了γ＇相的高温组织稳定性、液相线温度和固相线温度,但对结晶温度区间的影响较小。在单晶高温合金凝固过程中,以Mo代W降低了Al元素的显微偏析倾向,但对Re和Ta元素显微偏析行为的影响较小。同时,W和Mo在凝固时分别显著偏析于已凝固的固相和未凝固的液相。此外,以Mo代W增大了γ相和γ＇相的晶格常数,并降低了γ/γ＇错配度。Based on d-electron concept, a W-rich reinforced Ni based single crystal superalloy Alloy W and a Mo-rich reinforced Ni based single crystal superalloy Alloy Mo were designed. The thermodynamic calculation indicates that substituting Mo for W decreases the high temperature microsttucture stability, liquidus temperature and solidus temperature of γ＇ phase, while it has small influence on the crystallization temperature range. During the solidification of single crystal superalloy, substituting Mo for W decreases the microsegregation degree of Al element, while the effect on the microsegregation behaviors of Re and Ta elements are not significant. Meanwhile, W and Mo obviously segregate in solidified solid phase and unsolidified liquid phase during the solidification, respectively. Moreover, substituting Mo for W increases the lattice constants of γ phase and γ＇ phase and then the γ/γ＇ lattice misfit obviously decreases.

关 键 词：以Mo代W NI基单晶高温合金 凝固特性 晶格错配度 热力学计算 

分 类 号：TG146.15[一般工业技术—材料科学与工程]