单晶γ-TiAl合金微观滑移机制的研究

Study on the mechanism of micro-slip for γ-TiAl alloy with single crystal

针对单晶γ-TiAl合金微观滑移机制方面研究的不足,建立了单晶γ-TiAl合金单轴拉伸时晶体滑移几何模型,根据几何模型中各夹角之间的几何关系和由Weiss晶带法则给出的滑移方向,计算出了单滑移系中各个滑移方向上的Schmid因子;通过对比计算结果发现在设定条件下晶体更易产生滑移的方向为(001)[01-1]和(11-1)[110];在由主滑移系和交滑移系组成的双滑移系同时开动时,计算出了临界外加拉伸应变为0.633;通过数值模拟验证了所给出的单晶γ-TiAl合金单轴拉伸时的微观滑移机制的正确性。

Aimed at the deficiency of the study about the mechanism of micro-slip forγ-TiAl single crystal.The model of crystal slip forγ-TiAl single crystal with uniaxial tension was established in this paper.The Schmid factors along different slip directions were calculated based on the geometry relationship in model and the slip directions given by Weiss Zone Law.The result that crystal will be easier slip along (001)[01-1]and (11-1)[110] than other directions was obtained by comparing the calculated results.Besides,the result that critical value of external tensile strain under the given case of double slip system was 0.633 was got.Furthermore,the mecha-nism for micro-slip ofγ-TiAl alloy with monocrystal under uniaxial tension given in this paper is correct,which was verified by numerical simulation.