TiAl金属间化合物纳米粉末的相转变

Phase Transformation of TiAl Intermetallic Compound Nanoparticles

摘要:

对采用自悬浮定向流技术制备的TiAl金属间化合物纳米粉末进行真空退火，考察退火工艺参数对其相转变过程的影响。X射线衍射等分析表明：随着退火温度的升高以及退火时间的延长，纯a2-Ti3Al相纳米粉末向g-TiAl相转化的程度逐渐增加，其晶粒尺寸也逐渐变大。将其纳米粉末真空压制成块体也有助于上述相转变。对复相的纳米块体进行真空退火，可以得到纯g-TiAl相的纳米晶合金。

Abstract:

Experiments of vacuum annealing were carried out for nanoparticles of TiAl intermetallic compound prepared by the flow-levitation method. And the effect of annealing parameters on the phase transformation of TiAl alloy was investigated by X-ray diffraction analysis. The results show that more g-TiAl phase is transformed from a2-Ti3Al phase with the increasing of annealing temperature and time. And the grain size of two phases increases accordingly. This phase transformation is promoted after nanoparticles are compressed into a bulk by vacuum-pressing. The nanocrystalline alloy with pure g-TiAl phase is obtained after the bulk compressed from mixed phase nanoparticles is vacuum-annealed.