Structure of medium-range order in molten Al-Fe alloy

来源期刊：中国有色金属学报(英文版)2002年第5期

论文作者：丛红日 边秀房 李辉 秦敬玉

文章页码：947 - 951

Key words：Al-Fe alloy; MD simulation; medium-range order; structure factor; prepeak

Abstract: The molecular-dynamics (MD) simulation was carried out to investigate the structure of medium-range order (MRO) of a liquid Al₅Fe₂ alloy. Prepeak is observed in the structure factor S(Q), which is considered as the signature of MRO. Results from MD simulation and experiment agree well with each other, which proves reliability of the simulation. It is found from the calculated Ashcroft-Langreth structure factors that there exists strong interactional force between atom Al and Fe, which results in the great concentration fluctuation, i.e. the chemical order, in the liquid Al₅Fe₂. Both the chemical order parameter, α , and the Bhatis-Thornton（BT）structure factors indicate the preference for unlike-neighbor bonds. It is seen from the low-Q domain of S(Q) and the concentration-concentration structure factor S_CC(Q) that the prepeak mai, nly comes from the first peak of S_CC(Q). The structural model, which reflects the characteristic of MRO, is also constructed .