摘要
ＥＦＦＥＣＴＳＯＦＴＨＲＥＥＤＩＭＥＮＳＩＯＮＡＬＤＩＲＥＣＴＩＯＮＯＦＳＥＣＯＮＤＤＥＮＤＲＩＴＥＯＮＣＯＭＰＥＴＩＴＩＶＥＧＲＡＩＮＧＲＯＷＴＨＩＮＤＤ８ＳＵＰＥＲＡＬＬＯＹＬｉｕＺｈｉｙｉ；ＷｅｉＰｅｎｇｙｉ；ＦｕＨｅｎｇｚｈｉ（ＳｔａｔｅＫｅ...
Effects of three dimensional direction of DD8 nickel base single crystal superalloy on its competitive grain growth were investigaied by seed crystal method. Experimental results showed that <100> ×<100> (the first direction parallel to temperature gradient direction, the second direction perpendicular to temperature gradient direction and the contact plane of two half column seed crystal) grain competed with <110> ×<110> grain for growth under the conditions of G=250 K/cm, V = 47. 6 μm/s, and the former eliminated the later; however at the same experimental conditions, <100> ×<110) grain competed with <110> ×<100> grain for growth, and the later eliminated the former. Metallographic observations of cross sections of specimens showed that the migration velocity at various locations of grain boundaries was different in the process of competitive grain growth. It is indicated that the three dimensional direction of second dendrite is a key factor in the competitive grain growth, and the nonequilibrium grain boundary migration in the competitive grain growth is asseociated with the stagger between the grain dendrites.
出处
《中国有色金属学会会刊：英文版》
CSCD
1996年第2期111-116,共6页
Transactions of Nonferrous Metals Society of China
