(東北大學 材料冶金學院， 沈陽110004)
摘 要: 利用自蔓延高溫合成(SHS)技術， 制備了Al-3Ti-0.15C晶粒細化劑合金， 并通過DTA、 XRD、 SEM和EDX等手段分析了合金的組織形態(tài)及其形成機制。 結果表明SHS合成Al-3Ti-0.15C的過程為： 830℃時Ti（s）與Al(l)發(fā)生強烈的放熱反應， 在Al熔體中首先形成塊狀TiAl3相； SHS反應瞬間釋放的熱量， 使反應區(qū)迅速升溫，快速通過Al(l)+TiAl3(s)+C(s)三相共存的亞穩(wěn)態(tài)；然后以Al熔體為觸媒， 1020℃時活性Ti與C反應形成TiC粒子； TiAl3相在過飽和Al-Ti熔體中析出， 最終呈現(xiàn)針片狀。
關鍵字: SHS 技術； Al-3Ti-0.15C合金；組織形態(tài)； 形成機制
prepared by SHS
CAO Fu-rong, ZHAN Guo-chan
（ 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
