(1. 蘭州理工大學(xué) 甘肅省有色金屬新材料省部共建國家重點實驗室，蘭州 730050；2. 中國科學(xué)院金屬研究所, 沈陽 110016)
摘 要: 研究熱處理工藝對熱爆法合成Al-3%Ti-0.35%C 晶粒細化劑組織的影響機制。結(jié)果表明：Ti原子的擴散是控制熱處理的主要因素之一；400 ℃時脫溶反應(yīng)最先發(fā)生，經(jīng)過大約6 h反應(yīng)基本結(jié)束；當(dāng)Al3Ti滿足原子計量比時，其產(chǎn)物形態(tài)不發(fā)生改變，而當(dāng)晶界以及Al3Ti產(chǎn)物中存在過剩的鈦元素時，則細化劑的晶界及Al3Ti產(chǎn)物的周邊區(qū)域會有條件地發(fā)生擴散反應(yīng) ；當(dāng)在600 ℃連續(xù)保溫12 h以上時，脫溶反應(yīng)的Al3Ti產(chǎn)物重新溶解，晶界處的類共晶組織會消失，經(jīng)擴散反應(yīng)生成含Ti顆粒物質(zhì)。TiC顆粒未見變化。經(jīng)400 ℃保溫2 h熱處理的試樣的細化效果最佳。
關(guān)鍵字: Al-Ti-C晶粒細化劑；Al3Ti；TiC；熱處理工藝
（1. State Key Laboratory of Gansu Advanced Non-ferrous Metal Materials,Lanzhou University of Technology, Lanzhou 730050, China;2. Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China）
Abstract:Abstract: The influence mechanism of heat treatment on micro-structure of Al-3%Ti-0.35%C grain refiner prepared by thermal explosion method was researched. The results show that the Ti element diffusion is an important factor in heat treatment; the precipitation reaction is started firstly at 400 ℃ and is lasted for 6 h; when the Al3Ti particle meets the atomic computation, its configuration will hold for long. But when Ti element is superfluous at the grain boundary or border area of Al3Ti, the diffusion reaction will occur in this field at some condition. When the grain refiner holds for more than 12 h at 600 ℃, some particles that contain Ti element are obtained at the grain boundary by diffusion reaction, the eutectic-like structure and the product of precipitation reaction will disappear. The configuration of TiC particle can’t transform under the test condition. The refiner processed by the heat treatment that is held for 2 h at 400 ℃ has a good refining performance.
Key words: Al-Ti-C grain refiner; Al3Ti; TiC; heat treatment process
