铝熔体中原位反应生成TiC颗粒的机制分析  

Analysis of the Formation Mechanism of TiC Particles Produced by In Situ Reaction in Molten Aluminum

作　　者：杨滨[1,2,3] 王玉庆[1,2,3] 张键 周本濂[1,2,3] 

机构地区：[1]中国科学院金属研究所 [2]南昌大学 [3]中国科学院国际材料物理中心

出　　处：《稀有金属材料与工程》1997年第6期12-17,共6页Rare Metal Materials and Engineering

基　　金：国家自然科学基金

摘　　要：借助ＸＲＤ、ＥＰＭＡ、ＴＥＭ和ＳＥＭ等分析测试手段对铝熔体中原位反应合成ＴｉＣ进行的研究表明：（１）形成Ａｌ３Ｔｉ放出的热量可能是引发后续ＴｉＣ反应的原因之一；（２）整个反应过程中，扩散机制和溶解－析晶机制实际上都存在。在相对较低的温度区时，是由较慢的扩散过程控制整个反应。这时，随压制块温度升高，首先发生３Ａｌ（ｌ）＋Ｔｉ（ｓ）→Ａｌ３Ｔｉ的反应，然后通过该反应的反应热引发ＴｉＣ的反应；而高温区时。The formation mechanism to TiC particles formed by in situ reaction in molten aluminum is studied by means of XRD, EPMA, TEM and SEM techniques in this paper The results reveal that (1) the heat liberated by the reaction 3Al(1)+Ti(s)→Al3Ti can ignite the reaction Ti+C→TiC; (2)diffusion or/and solution-precipitation mechanisms, two well-known mechanisms of TiC particle formation in Self-propagating High-temperature Synthesis(SHS), are thought to be in operation At lower temperatures, the reaction leading to TiC particle formation is controlled by a diffusion mechanism of relatively slower velocity In this regime, the aluminum powders melt with increasing temperature of the preform, thereby igniting TiC particle reaction At the higher temperatures, the reaction Ti+C→TiC is controlled by the solution-precipitation mechanism, ie the diffusion and solution-precipitation mechanisms are both present in this regime

关 键 词：铝熔体 复合材料 原位反应 碳化钛 

分 类 号：TB333[一般工业技术—材料科学与工程]