徐向俊,宋霖,梁永峰,林均品

• 1:中原工学院材料与化工学院
• 2:北京科技大学新金属材料国家重点实验室

摘要(Abstract)：

通过扫描和透射电镜研究了铸造Ti-45Al-8Nb-0.2W-0.2B-0.02Y合金中Nb偏析区的相结构及其经中温和高温热处理后的相变规律。结果表明,铸造合金中的偏析区由约1μm大小的ωo相(B82结构)及其所在的βo(B2结构)与细小的ω相关相混杂而成的基体组成。中温较长时间处理后合金的Nb偏析区部分转变为γ相,已经发现3种βo(ω)→γ相变机制,即由基体的片层外延生长成为等轴γ、βo直接形成γ以及与已经存在的γ形成真孪晶后向βo推进。剩余偏析区表现为βo内分布着ωo或表现为纯的βo相。高温较短时间处理可以消除Nb偏析区,使偏析区由βo及ωo相关相转变为α2相。

关键词(KeyWords)： 金属间化合物;热处理;显微组织;相变

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金(U1204508);; 国家重点基础研究发展(973)计划(2011CB605501)

作者(Author): 徐向俊,宋霖,梁永峰,林均品

DOI: 10.13289/j.issn.1009-6264.2015.08.015

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