(1、湖南大學(xué)化學(xué)化工系；
2.應(yīng)用物理系，長(zhǎng)沙410082)
摘 要: 采用分子動(dòng)力學(xué)方法對(duì)液態(tài)金屬Al 及其凝固過(guò)程中的微觀結(jié)構(gòu)轉(zhuǎn)變特性進(jìn)行了模擬研究， 發(fā)現(xiàn)在1 800～3 50K的溫度區(qū)間內(nèi)，對(duì)全局結(jié)構(gòu)組態(tài)起重要作用的HA鍵型組態(tài)有1551、1541、1431、1311、1321和1422等，其中以1551鍵型組態(tài)最為顯著，它在全過(guò)程的微觀結(jié)構(gòu)轉(zhuǎn)變中起著主導(dǎo)作用，是其雙體分布函數(shù)g(r)曲線的第二峰出現(xiàn)由光滑正弦峰→平臺(tái)→分裂為二個(gè)次峰的轉(zhuǎn)變過(guò)程的決定性因素。
關(guān)鍵字: 液態(tài)金屬 凝固過(guò)程 微觀結(jié)構(gòu)轉(zhuǎn)變 計(jì)算機(jī)模擬
國(guó)家自然科學(xué)基金（編號(hào)：5917142）和湖南省自然科學(xué)基金（編號(hào)：94-028）資助項(xiàng)目
收稿日期：1996-12-19；修回日期：1997-02-15 李基永，女，54 歲，副教授
（1.Department of Chemistry,Hunan University, Changsha 410012
2.Department of Physics, Hunan University, Changsha 410012）
Abstract:A simulation study on the transition properties of microstructures in liquid metal Al and its solidification process has been performed by molecular dynamics method. It has been found that in the range of temperature of 1800～350K , the 1551, 1541, 1431, 1311, 1321 and 1422 bond-types represented by Honeycutt -Andersen(HA) index play an important role for the entire structure configuration. Of these bond-types the 1551 bond-type is the most remarkale, which plays a leading role during the whole process of microstructure transitions and is the decisive factor for the second peak of the pair distribution function g(r) being changed from a smooth sine peak into two split secondary peaks via a platform during the transition process.
Key words: liquid metal solidification process microstructure transition computer simulation
