Three ternary alloys with composition of Mg-(11-13)Gd-1Zn (mass fraction, %) have been prepared and their microstructures and mechanical properties have been also investigated. The results showed that the as cast microstructure of the three alloys consists of α-Mg matrix, (Mg, Zn)3Gd eutectic and a 14H long--period stacking ordered (14H--LPSO) phase. With the increase of Gd content the volume fraction of the (Mg, Zn)3Gd eutectic increases. After extrusion the (Mg, Zn)3Gd eutectic networks are destroyed and its broken particles are arranged in strips along the direction of extrusion, and the 14H--LPSO phase is distributed between (Mg, Zn)3Gd strips. Solid solution treatment at high temperature above 500 ℃ results in the dissolution of (Mg, Zn)3Gd phase into the matrix and the increase of the 14H-LPSO phase. After solution treated alloys are aged at temperature of 225 ℃ (T6 treatment) the volume fraction of the 14H-LPSO phase is further increased and both β' and β1 precipitates appear in the microstructure. Aging of as extruded alloys (T5 treatment) also causes the formation of β' and β1 precipitates but the volume fraction of the 14H--LPSO phase in the T5 treated specimens is lower than that in specimens after T6 treatment. High tensile strength combined with good ductility is obtained from the Mg--11Gd--1Zn alloy after T6 aging.
[1] Bae D H, Lee M H, Kim K T, Kim D H. J Alloy Compd, 2002; 342: 445
[2] Liu K, Zhang J H, Su G H, Tang D X, Rokhlin L L, Elkin F M, Meng J. J Alloy Compd, 2009; 481: 811
[3] Gao Y, Wang Q D, Gu J H, Zhao Y, Tong Y, Yin D D. J Alloy Compd, 2009; 477: 374
[4] Li D J, Zeng X Q, Dong J, Zhai C Q, Ding W J. J Alloy Compd, 2009; 468: 164
[5] Wu Y J, Zeng X Q, Lin D L, Peng L M, Ding W J. J Alloy Compd, 2009; 477: 193
[6] Apps P J, Karimzadeh H, King J F, Lorimer G. Scr Mater, 2003; 8: 1023
[7] Kawamura Y, Hayashi K, Inoue A, Masumoto T. Mater Trans, 2001; 42: 1171
[8] Itoi T, Seimiya T, Kawamura Y, Hirohashi M. Scr Mater, 2004; 51: 107
[9] Chino Y, Mabuchi M, Hagiwara S, Iwasaki H, Yamamoto A, Tsubakino H. Scr Mater, 2004; 51: 711
[10] Liu K, Meng J. J Alloys Compd, 2011; 509: 3299
[11] Yang Z, Li J P, Guo Y C, Liu T, Xia F, Zeng Z W, Liang M X. Mater Sci Eng, 2007; A454--455: 274
[12] Liu X B, Chen R S, Han E H. J Alloy Compd, 2008; 465: 232
[13] Han X Z, Xu W C, Shan D B. J Alloy Compd, 2011; 509: 8625
[14] Yin D D, Wang Q D, Gao Y, Chen C J, Zheng J. J Alloy Compd, 2011; 509: 1696
[15] Zhang S, Yuan G Y, Lu C, Ding W J. J Alloy Compd, 2011; 509: 3515
[16] Zheng L, Liu C M, Wan Y C, Yang P W, Shu X. J Alloy Compd, 2011; 509: 8832
[17] Yamasaki M, Sasaki M, Nishijima M, Hiraga K, Kawamura Y. Acta Mater, 2007; 55: 6798
[18] Honma T, Ohkubo T, Kamado S, Hono K. Acta Mater, 2007; 55: 4137
[19] Yamasaki M, Anan T, Yoshimoto S, Kawamura Y. Scr Mater, 2005; 53: 799
[20] Shao X H, Yang Z Q, Ma X L. Acta Mater, 2010; 58: 4760
[21] Hagihara K, Kinoshita A, Sugino Y, Yamasaki M, Kawamura Y, Yasuda H Y, Umakoshi Y. Acta Mater, 2010; 58: 6282
[22] Zeng X Q, Wu Y J, Peng L M, Lin D L, Ding W J, Peng Y H. Acta Metall Sin, 2010; 46: 1041
(曾小勤, 吴玉娟, 彭立明, 林栋樑, 丁文江, 彭赢红. 金属学报, 2010; 46: 1041)
[23] Matsuda M, Ando S, Nishida M. Mater Trans, 2005; 46: 361
[24] Antion C, Donnadieu P, Perrard F, Desehamps A, Tassin C, Piseh A. Acta Mater, 2003; 51: 5335
[25] Nie J F, Oh--ishi K, Gao X, Hono K. Acta Mater, 2008; 56: 6061
[26] Liu K, Zhang J H, Lu H, Tang D X, Rokhlin L L, Elkin F M, Meng J. Mater Des, 2010; 31: 210
