项目名称: 含第三组元共晶合金定向凝固中生长界面形貌的演化
项目编号: No.51201104
项目类型: 青年科学基金项目
立项/批准年度: 2013
项目学科: 金属材料学科
项目作者: 刘礼
作者单位: 上海交通大学
项目金额: 25万元
中文摘要: 晶体生长界面形貌是影响材料凝固组织的重要因素,因而其演化问题是凝固理论研究中的重点之一。大量研究表明,界面能及界面动力学各向异性对单相晶体生长形貌演化有决定性影响:界面各向异性强度大,则生长界面倾向于以树枝状形态生长;反之,则生长界面倾向于以海藻状形态生长。共晶合金以两相耦合方式凝固时,生长界面由两个不同相交替复合而成,导致其界面各向异性更加复杂。然而,迄今为止关于界面各向异性对共晶生长界面形貌演化影响的研究十分缺乏。本项目拟以含第三组元的Co-Sn以及Ag-Cu共晶合金为研究对象,研究它们在定向凝固过程中共晶生长界面形貌的演化问题。主要研究内容包括:(1)考察含第三组元共晶合金定向凝固中共晶生长界面形貌的形成及演化过程;(2)从凝固参数、第三组元、界面能及界面动力学各向异性出发,全面分析共晶生长界面形貌的演化机制。
中文关键词: 共晶合金;过冷凝固;定向凝固;界面形态;界面能各向异性
英文摘要: Growth interface morphology is an important influence factor for the solidification structures of materials. So the investigation of interface morphological evolution is an important part in the field of solidification theory. Amounts of researching results indicate that the anisotropies of interface energy and interface kinetics have decisive influence on the growth interface morphology of single-phase crystal: when the interface anisotropy is large the growth interface tends to grow with dendritic pattern;otherwise, with seaweed pattern. During the solidification of eutectic alloy, the eutectic growth interface is composed of two different phases, making the anisotropies of interface energy and interface kinetics more complicated.So far, however, the investigation about the influence of interface anisotropy on the eutectic growth interface morohpolgy is rare. This project plans to take Co-Sn and Ag-Cu eutectic alloys containing a third element as researching objects, and investigate the morphological evolution of growth interface in the directional solidification of them.The main contents include: (1) Explore the formation ang evolution processes of various eutectic growth interface morphologies in the directional solidification of binary eutectic alloys containing a third element; (2)Analyze the morphological
英文关键词: eutectic alloys;undercooling;directional solidification;interface morphology;interface enenrgy anisotropy