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)→Al3Ti 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, ie the diffusion and solution-precipitation mechanisms are both present in this regime
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
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
关键词
铝熔体
复合材料
原位反应
碳化钛
TiC/Al composite, in situ reaction, TiC particulate, formation mechanism
