(1. 兰州理工大学 甘肃省有色金属新材料省部共建国家重点实验室，兰州 730050；2. 中国科学院金属研究所, 沈阳 110016)
摘 要: 研究热处理工艺对热爆法合成Al-3%Ti-0.35%C 晶粒细化剂组织的影响机制。结果表明：Ti原子的扩散是控制热处理的主要因素之一；400 ℃时脱溶反应最先发生，经过大约6 h反应基本结束；当Al3Ti满足原子计量比时，其产物形态不发生改变，而当晶界以及Al3Ti产物中存在过剩的钛元素时，则细化剂的晶界及Al3Ti产物的周边区域会有条件地发生扩散反应 ；当在600 ℃连续保温12 h以上时，脱溶反应的Al3Ti产物重新溶解，晶界处的类共晶组织会消失，经扩散反应生成含Ti颗粒物质。TiC颗粒未见变化。经400 ℃保温2 h热处理的试样的细化效果最佳。
关键字: Al-Ti-C晶粒细化剂；Al3Ti；TiC；热处理工艺
（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
