首页 | 本学科首页   官方微博 | 高级检索  
     

Non-equilibrium solidification of undercooled Ni-31.44%Pb monotectic alloy melts
作者姓名:郑红星  谢辉  郭学锋
作者单位:School of Materials Science and Engineering,Xi′an University of Technology,Xi′an 710048,China
基金项目:Project ( 99JK2 2 3)supportedbytheScienceFoundationofShaanxiEducationCommitteeofChina
摘    要:1 INTRODUCTIONThesolidificationoftheundercooledalloymeltshasbeenthesubjectsofextensivestudyforover30a .Asanimportantwaytostudymode

关 键 词:高过度冷却  镍铅偏晶合金  结构变化  粒化机制  非平衡凝固

Non-equilibrium solidification of undercooled Ni-31.44%Pb monotectic alloy melts
ZHENG Hong xing,XIE Hui,GUO Xue feng.Non-equilibrium solidification of undercooled Ni-31.44%Pb monotectic alloy melts[J].Transactions of Nonferrous Metals Society of China,2002,12(1):38-42.
Authors:ZHENG Hong xing  XIE Hui  GUO Xue feng
Abstract:By using the method of molten glass denucleating combined with superheating cycling, solidification behavior of the bulk undercooled Ni-31.44%Pb monotectic alloy melts was systematically investigated. The results indicated that the undercooled monotectic alloy solidifies in form of dendrite essentially during the stage of rapid solidification and after recalescence, the residual melts between the dendrites solidify in the equilibrium mode. Within the achieved undercooling range, the solidification structures are classified into three categories. When the undercooling is less than 50K, the structures are composed of coarse dendrites and interdendritic lead phase. With the undercooling increasing into the range of 70~232K, the dendrite clusters are refined and fine lead particles separate out from the supersaturated primary dendrite arms because of solute trapping. When the undercooling exceeds 242K, the granular grains form and fine lead particles homogeneously distribute in the whole sample. Based on the observation of the solidification structures and the calculated results with BCT model, it is found that the granulation mechanism of the granular grains is owing to the primary dendrite disintegration and recrystallization.
Keywords:high undercooling  Ni  Pb monotectic alloy  structural evolution  granulation mechanism
本文献已被 CNKI 维普 万方数据 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号