摘要
基于耦合外应力场下的微观相场模型,研究了Ni_(75)Al_(7.5)V_(17.5)三元合金相变过程中相分解、生长过程中合金成分演化及应力作用下相间界面的定向迁移规律。研究表明:早期DO_(22)相长大所需的V来自于在L1_2相间有序畴界处,而后期则来自于其内部,且早期DO_(22)相长大的速度高于后期的长大速度;时效过程有5种异相间界面形成,而A类界面的迁移为相迁移的主要类型;相变初期A、B类界面较少,合金形貌变化不大,随着相变的进行,A类界面数量增加,相的生长及分解过程加剧,导致后期A类界面减少、B类界面增多,合金体系达到平衡状态;在压应力作用下,A类界面沿应力方向迁移,促进了DO_(22)相在此方向上的生长,导致合金"筏状"组织的形成。
Evolution of chemical composition during phase decomposition and growth and the mechanisms of the directional interface migration under exterior load for Ni_(75)Al_(7.5)V_(17.5) alloy were investigated, which was based on a microscopic phase-field method. The results show that V the growth of DO_(22) requires in the early stage comes from the ordering domain among L1_2, while it comes from the interior of L1_2 in the later stage, and the growth speed for DO_(22) in the early stage is faster than that in the later stage. They form five types of interfaces, and A-type is the main type for interface migration. It has a few A and B type interfaces in the early stage, and morphology changes little. With the rise of the A-type interface number, the growth and decomposition for phases accelerate, the number of A-type interface declines and the number of B-type interface increases, and the alloy reaches balance finally. A-type interface migrates along the stress direction under compressive stress; as a result, DO_(22) grows along this direction, and a rafting structure of the alloy forms.
引文
[1]Fratzl P,Penrose O,LEbowitz J.Journal of Statistical Physics[J],1999,95:1429
[2]Stallybrass C,Schneider A,Sauthoff G.Intermetallics[J],2005,13:1263
[3]Nabarro F R N.Metall Mater Trans A[J],1996,27:513
[4]Tetsu I,Daisuke K,Masahiko H et al.Acta Mater[J],2003,51:4033
[5]Socrate S,Parks D M.Acta Metall[J],1993,41:2185
[6]Takao Murakumo,Toshiharu Kobayashi,Yutaka Koizumi et al.Acta Materialia[J],2004,52:3737
[7]Cabet E,Pasturel A,Ducastelle F.Physical Review Letter[J],1996,76:3140
[8]Tomihisa K,Kanenoand Y.Intermetallics[J],2004,12:317
[9]Han G M,Yu J J,Sun Y L et al.Materials Science and Engineering A[J],2010,527:5383
[10]Xia P C,Yu J J,Sun X F et al.Journal of Alloys and Compounds[J],2007,443:125
[11]Hosford W F,Agrawal S P.Metall Trans[J],1975,6:487
[12]Cahn J W,Hilliard J E.Chem Phys[J].1958,28:258
[13]Chang J C,Allen S M.J Mater Res[J],1991,6:1843
[14]Nabarro F R N,Cress C M,Kotschy P.Acta Mater[J],1996,44:3189
[15]Johnson R A,Brown J R.Journal of Materials Research[J],1992,12:3213
[16]Wang Y,Khachaturyan A G.Acta Metall Mater[J],1995,43:1837
[17]Zhao Yuhong(赵宇宏),Chen Zheng(陈铮),Liu Bing(刘兵).Chinese Journal of Rare Metals(稀有金属)[J],2003,27:119
[18]Lu Yanli(卢艳丽),Chen Zheng(陈铮),Zhong Hanwen(钟汉文)et al.Rare Metal Materials and Engineering(稀有金属材料与工程)[J],2009,38(11):1890
[19]Yang Tao(杨涛),Chen Zheng(陈铮),Zhang Jing(张静)et al.Rare Metal Materials and Engineering(稀有金属材料与工程)[J],2013,42(9):1773
[20]Khachaturyan A G.Theory of Structural Transformation in Solids[M].New York:Wiley,1983:129
[21]Chen L Q,Khachaturyan A G.Scripta Metallurgica Materialia[J],1991,25:61
[22]Prikhodko S V,Carnes J D,Saak D G et al.Scr Mater[J],1997,38:67
[23]Miyazaki T,Imamura M,Kozati T.Mater Sci Eng[J],1982,54:9
[24]Singh J B,Sundararaman M,Banerjee S et al.Acta Mater[J],2005,53:1135
[25]Zapolsky H,Pareige C,Marteau L et al.Calphad[J],2001,25:125