劉 林2， 徐達(dá)鳴1, 李金山2
(1. 哈爾濱工業(yè)大學(xué) 金屬精密熱加工國防科技重點(diǎn)實(shí)驗(yàn)室，
哈爾濱 150001；
2. 西北工業(yè)大學(xué) 凝固技術(shù)國家重點(diǎn)實(shí)驗(yàn)室， 西安 710072)
摘 要: 在航空航天及能源領(lǐng)域有重要應(yīng)用價(jià)值的TiAl基合金， 由于其γ+α2片層結(jié)構(gòu)的特點(diǎn)， 采用定向凝固技術(shù)控制片層方向可以更好地發(fā)揮其潛能。 從相與組織選擇及晶體擇優(yōu)生長(zhǎng)特性角度， 討論了具有包晶反應(yīng)的高溫γ-TiAl合金的定向凝固與晶向控制， 分析了晶向控制中引晶、 合金化、 調(diào)節(jié)成分與凝固參量及它們的綜合作用所得到的結(jié)果與存在的問題，并提出了此領(lǐng)域今后應(yīng)注意的方面。
關(guān)鍵字: TiAl金屬間化合物； 定向凝固； 晶向控制
LIU Lin2， XU Da-ming1, LI Jin-shan2
（1. State Key Laboratory of Precision Hot Processing of Metals,
|Harbin Institute of Technology, Harbin 150001, China;
2. State Key Laboratory for Solidification Processing,
Northwestern Polytechnical University, Xi′an 710072, China）
Abstract:The directionally solidified microstructure of TiAl-based alloys which have potential applications in aerospace and energy industry is very helpful for improving its mechanical properties with respect to the orientational characteristic of γ+α2 lamellar. The orientation controlling of γ-TiAl during peritectic reaction or transformation was discussed from the view of the selection of phase and structure and the selected growth of crystal. The effects of seeding, alloying and adjusting of solidification parameters on the structure were analyzed. Many problems were revealed and that must be overcome in the future in order to get an optimum structure.
Key words: TiAl intermetallics; directional solidification; crystal orientation control
