冷却速率对Mg-Gd-Y-Zr合金凝固组织的影响(英文)  

Effect of Cooling Rate on the Solidified Microstructure of Mg-Gd-Y-Zr Alloy

作　　者：周吉学[1,2] 杨院生 童文辉[1] 王杰[1] 付俊伟[1] 汪彬[1] 

机构地区：[1]中国科学院金属研究所,辽宁沈阳110016 [2]山东科学院新材料研究所,山东济南250014

出　　处：《稀有金属材料与工程》2010年第11期1899-1902,共4页Rare Metal Materials and Engineering

基　　金：National Natural Science Foundation of China (50774075);National Science and Technology Support Plan Project (2006BAE04B01-4)

摘　　要：通过改变凝固过程中的冷却速率,研究了冷却速率对Mg-Gd-Y-Zr合金凝固组织与成分微观偏析的影响。随冷却速率提高,合金组织明显细化,初生相形貌由粗大等轴枝晶逐渐向细小树枝晶转变,合金凝固过程中形核率增加,合金晶粒尺寸逐渐减小;冷却速率的提高可以降低溶质元素的扩散速率,从而增加合金元素在枝晶干中的固溶度,减轻凝固过程中合金元素Gd与Y的微观偏析,同时使凝固过程中形成的共晶减少,共晶组织分布更加弥散、均匀。The cooling rate has significant effects on the microstructure of Mg-Gd-Y-Zr alloy. It is found that the increase of cooling rate can refine the solidified microstructure obviously. The grains are refined and the morphology of the primary phases is changed from the coarse to the thin. With the increase of cooling rate, the eutectic distributes more homogeneously and its volume fraction decreases. Higher cooling rate can increase the solid solubility, which contributes to the reduction of dendritic segregation of solutes of Gd and Y in Mg-Gd-Y-Zr alloy. Copyright © 2010, Northwest Institute for Nonferrous Metal Research. Published by Elsevier BV. All rights reserved.

关 键 词：冷却速率 合金凝固组织 MICROSTRUCTURE cooling rate 合金凝固过程 MICROSTRUCTURE 微观偏析 合金元素 solid solubility volume fraction 等轴枝晶 significant 组织分布 溶质元素 扩散速率 晶粒尺寸 合金组织 共晶 形核率 相形貌 

分 类 号：TG111.4[金属学及工艺—物理冶金]