采用弹性应力-应变有限元方法计算了[011]取向单晶镍基合金中γ/γ'两相共格界面的von Mises应力及应变能密度的分布特征, 研究了施加拉应力对γ/γ'两相界面von Mises应力分布及γ'相定向粗化规律的影响. 结果表明: [011]取向单晶镍基合金经热处理后, 组织结构是立方γ'相以共格方式嵌镶在 γ基体相中, 并沿<100>方向规则排列. 当沿[011]方向施加拉应力时, 与近(010)γ'晶面的基体通道相比, 近(001)γ'晶面的基体通道有较大的von Mises应力, 在主应力分量的作用下, 与 (010)γ'晶面相比较, (001)γ'晶面沿[010]γ'方向发生较大的晶格扩张应变, 可诱捕较大半径的Al原子和Ti原子, 是促使γ'相沿[001]方向定向生长成为纤维状筏形组织的主要原因.
By means of the elastic stress-strain finite element method (FEM), the distribution features of the von Mises stress, strain energy density and the influences of the applied stress on the von Mises stress at γ/γ' phases interface and γ' phase directionally coarsening regularity in a [011] oriented single crystal nickel-based superalloy were investigated. Results show that after heat treatment, the microstructure of the superalloy consists of the cubic γ' phases embedded coherently in the γ matrix, and γ' phases arranged regularly along the <100> direction. Compared to the matrix channel near (010)γ' plane, the bigger von Mises stress are produced within the matrix channel near (001)γ' plane when the tensile stress is applied along the [011] direction. Compared to (010)γ' plane, the larger expanding lattice strain occurs on the (001)γ' plane along the [010]γ' direction under the action of the principal stress component, resulting in the Al, Ti atoms with bigger radius to be trapped by the larger strain zone, which is the main reason of promoting the γ' phase grown directionally into the strip-like rafted structure.
[1] Feng H, Biermann H, Mughrabi H. Metall Mater Trans, 2000; 31A: 585
[2] Yu X F, Tian S G, Du H Q, Yu H C, Wang M G, Shang L J, Cui S S. Mater Sci Eng, 2009; A506: 80
[3] Tien J K, Copley S M. Metall Trans, 1971; 2: 543
[4] Buffiere J Y, Ignat M. Acta Metall Mater, 1995; 43: 1791
[5] Pollock T M, Argon A S. Acta Metall Mater, 1994; 42: 1859
[6] Kuhn H A, Biermann H, Ungar T. Acta Metall Mater, 1991; 39: 2783
[7] Biermann H, Strehler M, Mughrabi H. Metall Mater Trans, 1996; 27A: 1003
[8] Tian S G, Zhang J H, Yang H C, Xu Y B, Hu Z Q. J Aeronautic Mater, 2000; 20: 1
(田素贵, 张静华, 杨洪才, 徐永波, 胡壮麒. 航空材料学报, 2000; 20: 1)
[9] Tian S G, Chen C R, Yang H C, Hu Z Q. Acta Metall Sin, 2000; 36: 465
(田素贵, 陈昌荣, 杨洪才, 胡壮麒. 金属学报, 2000; 36: 465)
[10] Tian S G, Wang M G, Yu H C, Yu X F, Li T, Qian B J. Mater Sci Eng, A527: 4458
[11] Sha Y H, Chen C R, Zhang J H, Xu Y B, Hu Z Q. Acta Metall Sin, 1999; 36: 254
(沙玉辉, 陈昌荣, 张静华, 徐永波, 胡壮麒. 金属学报, 1999; 36: 254)
[12] Zhou L, Yu X L. Trans Shenyang Ligong Univ, 2008; 27: 1
(周丽, 于晓琳. 沈阳理工大学学报, 2008; 27: 1)
[13] Nabarro F R N. Metall Mater Trans, 1996; 27A: 513
[14] Tian S G, Zhang J H, Yang H C, Hu Z Q. Mater Sci Technol, 2000; 16, 451
[15] Shui L, Yang Y H, Yu J J. Mater Mech Eng, 2009; 33: 6
(水丽, 杨彦红, 于金江. 机械工程材料, 2009; 33: 6)
[16] Shui L, Jin T, Tian S, Hu Z Q. Rare Met Mater Eng, 2009; 38: 826
(水丽, 金涛, 田素贵, 胡壮麒. 稀有金属材料与工程, 2009; 38: 826)
