|
|
MICROSTRUCTURE EVOLUTION AND ORIENTATION ANALYSIS OF HYPEREUTECTIC Al-Al2Cu ALLOY UNDER DIRECTIONAL SOLIDIFICATION |
GAO Ka, LI Shuangming( ), FU Hengzhi |
State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi′an 710072 |
|
Cite this article:
GAO Ka, LI Shuangming, FU Hengzhi. MICROSTRUCTURE EVOLUTION AND ORIENTATION ANALYSIS OF HYPEREUTECTIC Al-Al2Cu ALLOY UNDER DIRECTIONAL SOLIDIFICATION. Acta Metall Sin, 2014, 50(8): 962-970.
|
Abstract Dendrite is a fundamental growth pattern in alloy solidification. Normally, dendrites with a specific growth orientation which can remarkably influence casting properties have attracted many great interests. The previous investigations mainly focus on the growth of simple monophase dendrites solid solution. For complex intermetallics in solidification, the correlation between processing parameters and microstructure morphologies with the preferred growth directions has not been shed a light. In this work, considering intermetallic Al2Cu phase has crystalline anisotropy and can exhibit colorfully complicated growth morphologies with specific growth direction in different solidification conditions, the primary Al2Cu phase growth behavior of Al-40%Cu (mass fraction) hypereutectic alloy was investigated by using a high thermal gradient directional solidification apparatus. The Al2Cu phase growth behavior in the experiments included its change in growth morphology and orientation transition. With solidification distance increasing, due to the alloy liquid composition ahead of the solid/liquid interface approaching the eutectic point, the primary Al2Cu dendrite transited from regular faceted V-shaped morphology to the entirely coupled eutectic at 10 μm/s. Its growth direction changed from [110] direction to the normal direction of (121) plane. The EBSD result indicated that the [001] direction of Al2Cu phase was along the direction of heat flux. As the growth rate was changed abruptly from 10 to 2 μm/s, the alloy liquid composition ahead of the solid/liquid interface increased firstly and then decreased to the eutectic point. It caused that the primary Al2Cu dendrite transited from regular faceted V-shaped morphology to long smooth lath morphology, and finally disappeared to form the entirely coupled eutectic. Moreover, the growth direction of Al2Cu phase changed from [110] direction to [001] direction. The experimental results show that the directional solidification process parameter is the dominant factor affecting the final morphology and growth direction of dendrites.
|
Received: 25 November 2013
|
|
Fund: Supported by National Natural Science Foundation of China (Nos.50971101 and 51074127) and Fund of State Key Laboratory of Solidification Processing in NWPU (No.34-TP-2009) |
[1] |
Salgado-Ordorica M A, Phillion A B, Rappaz M. Metall Mater Trans, 2013; 44A: 2699
|
[2] |
Warren J. Nat Mater, 2006; 5: 595
|
[3] |
Haxhimali T, Karma A, Geonales F, Rappaz M. Nat Mater, 2006; 5: 660
|
[4] |
Yan X Q, Liu S X, Long W M, Huang J L, Zhang L Y, Chen Y. Mater Des, 2013; 45: 440
|
[5] |
Sharma C, Dwivedi D K, Kumar P. Mater Des, 2013; 43: 136
|
[6] |
Sass V, Glatzel U, Feller-Kniepmeier M. Acta Mater, 1996; 44: 1969
|
[7] |
Du Y Z, Zheng M Y, Xu C, Qiao X G, Wu K, Liu X D, Wang G J, Lv X Y. Mater Sci Eng, 2013; A576: 10
|
[8] |
Matsunawa A, Katayama S, Simidzu H. Trans Joining Weld Res Inst, 1990; 19: 71
|
[9] |
Asta M, Beckermann C, Karma A, Kurz W, Napolitano R, Plapp M, Purdy G, Rappaz M, Trivedi R. Acta Mater, 2009; 57: 942
|
[10] |
Zhu W W, Ren Z M. Mater Sci Eng, 2006; A441: 185
|
[11] |
Yilmaz F, Elliott R. J Cryst Growth, 1984; 66: 466
|
[12] |
Quan Q R, Li S M, Fu H Z. Acta Metall Sin, 2010; 46: 500
|
|
(全琼蕊, 李双明, 傅恒志. 金属学报, 2010; 46: 500)
|
[13] |
Gao K, Li S M, Fu H Z. Adv Mater Lett, 2011; 2: 369
|
[14] |
Massalski T B, Okamoto H, Subramanian P R, Kacprzak L. Binary Alloy Phase Diagrams. 2nd Ed., Materials Park, Ohio: ASM International Publications, 1990: 141
|
[15] |
Zhao P, Li S M, Fu H Z. Acta Metall Sin, 2012; 48: 35
|
|
(赵 朋, 李双明, 傅恒志. 金属学报, 2012; 48: 35)
|
[16] |
Ting L, Li S M, Fu H Z. Rare Met Mater Eng, 2007; 36: 617
|
|
(唐 玲, 李双明, 傅恒志. 稀有金属材料与工程, 2007; 36 : 617 )
|
[17] |
Jackson K A, Hunt J D. Trans Metall Soc AIME, 1966; 236: 1129
|
[18] |
Li X, Ren Z, Fautrelle Y, Zhang Y D, Esling C. Acta Mater, 2010; 58: 1409
|
[19] |
Li X, Ren Z, Fautrelle Y. Acta Mater, 2006; 54: 5353
|
[20] |
Sun Z, Zhang L, Guo M, Vleugels J, Van der Biest O, Blanpain B. Europhys Lett, 2010; 89: 64002
|
[21] |
Kraft R W, Albright D L. Tran Metall Soc AIME, 1961; 221: 97
|
[22] |
Hamar R, Lemaignan C. J Cryst Growth, 1981; 53: 587.
|
[23] |
Fu H Z,Guo J J,Liu L,Li J S. Directional Solidification and Processing of Advanced Materials. Beijing: Science Press, 2008: 594
|
|
(傅恒志,郭景杰,刘 林,李金山. 先进材料定向凝固. 北京: 科学出版社, 2008: 594)
|
[24] |
Stefanescu D M. Science and Engineering of Casting Solidification. 2nd Ed., Berlin: Springer, 2009: 176
|
[25] |
Dai F P, Wei B B. Sci China, 2009; 39G: 1544
|
|
(代富平, 魏炳波. 中国科学, 2009; 39G: 1544)
|
[26] |
Gao K, Li S M, Xu L, Fu H Z. Cryst Res Technol, 2014; 49: 167
|
No Suggested Reading articles found! |
|
|
Viewed |
|
|
|
Full text
|
|
|
|
|
Abstract
|
|
|
|
|
Cited |
|
|
|
|
|
Shared |
|
|
|
|
|
Discussed |
|
|
|
|