摘要
评述Ni 1 8Al 4Ti合金由于形成γ’基体 /γ共格析出颗粒的独特组织结构而在高温蠕变试验中所表现出来的长时间“零蠕变”现象。应用Hirsch等人关于高层错能基体 /低层错能共格析出颗粒的强化理论 ,可以对此现象作出很好解释 ,并由此指出一种值得重视的有效高温强化机制。对获得这种组织结构所需的化学成分和工艺条件也作了讨论 ,认为快速凝固工艺是实现这类合金的重要手段之一。
The “nil creep” phenomenon of Ni 18Al 4Ti alloy at high temperature was due to the formation of unique microstructure with γ particles precipitated in γ′ matrix.The theory proposed by Hirsch et al about strengthening mechanism of low SFE precipitates in high SFE matrix could be used to explain this phenomenon,therefore,an effective and meritorious high temperature strengthening mechanism was suggested.The necessary chemical composition and process conditions to obtain such structure were discussed,it was indicated that rapid solidification technology would be an important means to produce this kind of alloy.
出处
《上海金属》
CAS
2000年第6期3-10,共8页
Shanghai Metals
关键词
镍基高温合金
蠕变
位错
强化机制
Ni based High Temperature Alloy,Creep,Dislocation,Strengthening Mechani
