(1. 東北大學 材料與冶金學院，沈陽 110004；
2. 吉林大學 材料科學與工程學院，吉林130025)
摘 要: 設(shè)計了一種電致伸縮式單軸超聲懸浮反應(yīng)系統(tǒng)，在Al-Ti熔體中形成超聲駐波，使C粉末懸浮在合金熔體中進行TiC合成反應(yīng)，以制備Al-3Ti-0.15C晶粒細化劑。通過組織觀察和聲壓分析，研究了C粉末的懸浮情況、合金的組織形態(tài)及其形成機制。結(jié)果表明：只有在聲輻射功率較小的時候，超聲波在輻射塊與反射板間的熔體中形成聲壓節(jié)點，在聲壓梯度作用下，使C和TiAl3能穩(wěn)定地懸浮在聲壓節(jié)點處，而聲功率較大時，駐波的二次諧波增加，聲壓節(jié)點消失，C粉末的穩(wěn)定性破壞；C粉末的反應(yīng)過程為：超聲的空化效應(yīng)使TiAl3溶解形成活性Ti，并通過Ti、C發(fā)生合成反應(yīng)形成TiC相，同時，對TiC粒子具有熱激活作用。
關(guān)鍵字: Al-Ti-C合金；晶粒細化劑；超聲懸浮；反應(yīng)機制
TiC synthesis reaction in Al-Ti melt
（1. School of Materials and Metallurgy, Northeastern University,
Shenyang 110004, China;
2. School of Materials Science and Engineering, Northeastern University,
Jilin 130025, China）
Abstract:An electrostriction type uniaxial ultrasonic levitation reaction system was designed. Ultrasonic stationary wave is formed to suspend C powder in Al-Ti melt to perform TiC synthesis reaction and the Al-3Ti-0.15C grain refiner alloy was prepared. The suspension state of C powder, microstructural morphology and its formation mechanism of such alloy were investigated after microstructural observation and sound pressure analysis. The results show that only when the sound radiation power is small, the sound pressure node is formed between radiation block and reflection board by ultrasonic. Under the action of sound pressure gradient, C powder and TiAl3 can suspend stably in the sound pressure node. When sound power is large, the second harmonic of stationary increases, the sound pressure node disappears and the levitation stability of C powder is destroyed. The reaction process of C powder is that ultrasonic cavitation effect makes TiAl3 be dissolved to form active Ti, and TiC phase is formed through the synthesis reaction of Ti and C, meantime, such effect has thermal activation influence on TiC particles.
Key words: Al-Ti-C alloy; grain refiner; ultrasonic levitation; synthesis mechanism
