Abstract
The dynamic solidification of ternary Ag38.5Cu33.4Ge28.1 eutectic alloy within a 35 kHz ultrasonic field is investigated and compared with both its equilibrium solidification by DSC method and its rapid solidification in drop tube. The volume fractions of the primary (Ge) phase and pseudobinary (Ag+ɛ 2) eutectic solidified within ultrasonic field are larger than those formed under equilibrium state, whereas that of ternary (Ag+ɛ 2+Ge) eutectic exhibits the reverse trend. During rapid solidification, the liquid alloy droplet directly solidifies into ternary (Ag+ɛ 2+Ge) eutectic if its diameter is smaller than 350 μm. The ultrasound stimulates the nucleation of alloy melt and prevents the bulk undercooling. With the increase of sound intensity, the primary (Ge) phase transfers from faceted dendrites to nonfaceted blocks with blunt edges, and its grain size is remarkably reduced. Both pseudobinary (Ag+ ɛ 2) and ternary (Ag+ɛ 2+Ge) eutectics experience a morphological transition from regular to anomalous structures. This indicates that their cooperative growth mode is replaced by independent growth of eutectic phases under the combined effects of cavitation and acoustic streaming. The ultrasound also shows a prominent coarsening effect to the pseudobinary (Ag+ɛ 2) and ternary (Ag+ɛ 2 +Ge) eutectics.
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References
Campell J. Effects of vibration during solidification. Int Metall Rev, 1981, 26: 71–103
Abramov O V. Ultrasound in Liquid and Solid Metals. Boca Raton: CRC Press, 1994. 1–35
Chinnama R K, Fauteux C, Neuenschwander J, et al. Evolution of the microstructure of Sn-Ag-Cu solder joints exposed to ultrasonic waves during solidification. Acta Mater, 2011, 59: 1474–1481
Luque de Castro M D, Priego-Capote F. Ultrasound-assisted crystallization (sonocrystallization). Ultrason Sonochem, 2007, 14: 717–724
Das A, Kotadia H R. Effect of high-intensity ultrasonic irradiation on the modification of solidification microstructure in a Si-rich hypoeutectic Al-Si alloy. Mater Chem Phys, 2011, 125: 853–859
Abramov V, Abramov O, Bulgakov V, et al. Effects of ultrasonic vibration on the iron-containing intermetallic compounds of high silicon aluminum alloy with 2% Fe. Mater Lett, 1998, 37: 27–34
Ramirez A, Qian M, Davies B, et al. Potency of high-intensity ultrasonic treatment for grain refinement of magnesium alloys. Scripta Mater, 2008, 59: 19–22
Puga H, Teixeira J C, Barbosa J. The combined effect of melt stirring and ultrasonic agitation on the degassing efficiency of AlSi9Cu3 alloy. Mater Lett, 2009, 63: 2089–2092
Xu H, Jian X, Meek T T, et al. Effect of power ultrasound on solidification of aluminum A356 alloy. Mater Lett, 2005, 58: 190–193
Zhai W, Hong Z Y, Xie W J, et al. Ternary eutectic growth of Ag-Cu-Sb alloy within ultrasonic field. Sci China Ser G-Phys Mech Astron, 2007, 50: 500–508
Chow R, Bilindt R, Chivers R. A study on the primary and secondary nucleation of ice by power ultrasound. Ultrasonics, 2005, 43: 227–230
Zhong G, Wu S, Jiang H, et al. Effects of ultrasonic vibration on the iron-containing intermetallic compounds of high silicon aluminum alloy with 2% Fe. J Alloys Compd, 2010, 492: 482–487
Kandemir S, Helen V A, Lawes S D A. Effect of ultrasonic treatment on the microstructure of A201 aluminium alloy for thixoforming. AIP Conf Proc, 2011, 1353: 1063–1068
Li Y L, Feng H K, Cao F R, et al. Effect of high density ultrasonic on the microstructure and refining property of Al-5Ti-0.25C grain refiner alloy. Mater Sci Eng A, 2008, 487: 518–523
Wannasin J, Martinez R A, Flemings M C. Grain refinement of an aluminum alloy by introducing gas bubbles during solidification. Scripta Mater, 2006, 55: 115–118
Liu X, Osawa Y, Takamori S, et al. Microstructure and mechanical properties of AZ91 alloy produced with ultrasonic vibration. Mater Sci Eng A, 2008, 487: 120–123
Qian M, Ramirez A, Das A, et al. The effect of solute on ultrasonic grain refinement of magnesium alloys. J Cryst Growth, 2010, 312: 2267–2272
Bantibhai P, Chaudhari G P, Bhingole P P. Microstructural evolution in ultrasonicated AS41 magnesium alloy. Mater Lett, 2012, 66: 335–338
Gao D, Li Z, Han Q, et al. Effect of ultrasonic power on microstructure and mechanical properties of AZ91 alloy. Mater Sci Eng A, 2009, 502: 2–5
Aghayani M K, Niroumand B. Effects of ultrasonic treatment on microstructure and tensile strength of AZ91 magnesium alloy. J Alloys Compd, 2011, 509: 114–122
Tolnai D, Townsend P, Requena G, et al. In situ synchrotron tomographic investigation of the solidification of an AlMg4.7Si8 alloy. Acta Mater, 2012, 60: 2568–2577
Amberger D, Eisenlohr P, Goken M. On the importance of a connected hard-phase skeleton for the creep resistance of Mg alloys. Acta Mater, 2012, 60: 2277–2289
Toda H, Nishimura T, Uesugi K, et al. Influence of high-temperature solution treatments on mechanical properties of an Al-Si-Cu aluminum alloy. Acta Mater, 2010, 58: 2014–2025
Nagels E, Van Humbeeck J, Froyen L. The Ag-Cu-Ge ternary phase diagram. J Alloys Compd, 2009, 482: 482–487
Ruan Y, Dai F P, Wei B. Formation mechanism of the primary faceted phase and complex eutectic structure within an undercooled Ag-Cu-Ge alloy. Appl Phys A, 2010: 104: 275–287
Wang N, Wei B. Rapid crystallization and growth mechanisms of highly undercooled Ag-Cu-Ge ternary alloy. J Cryst Growth, 2003, 247: 576–586
Villars P, Prince A, Okamoto H. Handbook of Ternary Alloy Phase Diagrams. ASM International (Materials Park) CD Vision, 1995
Witusiewicz V T, Sturz L, Hecht U, et al. Thermodynamic description and unidirectional solidification of eutectic organic alloys: I. Succinonitrile-(D)camphor system. Acta Mater, 2004, 52: 4561–4571
Curiotto S, Battezzati L, Johnson E, et al. Thermodynamics and mechanism of demixing in undercooled Cu-Co-Ni alloys. Acta Mater, 2007, 55: 6642–6650
Kurz W, Fisher D J. Fundamentals of Solidification. 3rd ed. Switzerland: Trans Technol Publications Ltd, 1989. 16–40
Hickling R. Transient, high-pressure solidification associated with cavitation in water. Phys Rev Lett, 1994, 73: 2853–2855
Krivilyov M, Volkmann T, Gao J, et al. Multiscale analysis of the effect of competitive nucleation on phase selection in rapid solidification of rare-earth ternary magnetic materials. Acta Mater, 2012, 60: 112–122
Lee E, Ahn S. Solidification progress and heat transfer analysis of gas-atomized alloy droplets during spray forming. Acta Metall Mater, 1994, 42: 3231–3243
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Contributed by WEI BingBo (CAS Academician)
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Zhai, W., Hong, Z., Mei, C. et al. Dynamic solidification mechanism of ternary Ag-Cu-Ge eutectic alloy under ultrasonic condition. Sci. China Phys. Mech. Astron. 56, 462–473 (2013). https://doi.org/10.1007/s11433-013-5004-x
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DOI: https://doi.org/10.1007/s11433-013-5004-x