(东北大学 材料冶金学院， 沈阳110004)
摘 要: 利用自蔓延高温合成(SHS)技术， 制备了Al-3Ti-0.15C晶粒细化剂合金， 并通过DTA、 XRD、 SEM和EDX等手段分析了合金的组织形态及其形成机制。 结果表明SHS合成Al-3Ti-0.15C的过程为： 830℃时Ti（s）与Al(l)发生强烈的放热反应， 在Al熔体中首先形成块状TiAl3相； SHS反应瞬间释放的热量， 使反应区迅速升温，快速通过Al(l)+TiAl3(s)+C(s)三相共存的亚稳态；然后以Al熔体为触媒， 1020℃时活性Ti与C反应形成TiC粒子； TiAl3相在过饱和Al-Ti熔体中析出， 最终呈现针片状。
关键字: SHS 技术； Al-3Ti-0.15C合金；组织形态； 形成机制
prepared by SHS
（ School of Materials and Metallurgy, Northeastern University, Shenyang 110004, China）
Abstract: Al-3Ti-0.15C grain refiner alloy was prepared by self-propagating high-temperature synthesis technique. The morphology of the alloy and its formation mechanism were studied by means of DTA, XRD, SEM and EDX. The results show that during the process of synthesizing Al-3Ti-0.15C by SHS, block-typed TiAl3 phase is formed firstly in Al melt; then the melt temperature is raised immediately by the heat released from SHS reaction and passes metastable sates of Al(l)+TiAl3(s)+C(s), taking Al melt as catalyst to form TiC particles through active Ti and C reaction at 1020℃. TiAl3 phase precipitates from over-saturated Al-Ti melt and takes on flaky shape.
Key words: SHS technique; Al-3Ti-0.15C alloy; structural morphology; formation mechanism
