Effect of solidification temperature range on the dendritic growth mode
Tóm tắt
Electromagnetic levitation technique was used to undercool bulk samples of Co-20% Cu and Co-60% Cu alloys and high undercoolings up to 303 and 110 K were achieved, respectively. The dendritic growth velocities were measured as a function of undercooling. The dendrite growth velocity of the Co-20% Cu alloy was much higher than that of the Co-60% Cu alloy. The experimental data were analyzed on the basis of the LKT/BCT dendritic growth model by taking into account non-equilibrium interface kinetics. It has been revealed that a transition from solute diffusion controlled dendritic growth to thermal diffusion controlled dendritic growth occurs at an undercooling of about 66 K for the Co-20% Cu alloy, whereas the dendrite growth in Co-60% Cu alloy proceeds in a solute diffusion controlled mode within a large solidification temperature range, and the solutal undercooling plays a dominant role. It is thus deduced that certain distinct solidification temperature ranges may be responsible for the different solidification modes for the two alloys.
Tài liệu tham khảo
Ben-Jacob E, Garik P. The formation of patterns in non-equilibrium growth. Nature, 1990, 343: 523–530
Willnecker R, Herlach D M, Feuerbacher B. Evidence of nonequilibrium processes in rapid solidification of undercooled metals. Phys Rev Lett, 1989, 62: 2707–2710
He G, Eckert J, Löser W, et al. Novel Ti-base nanostructure-dendrite composite with enhanced plasticity. Nat Mater, 2003, 2: 33–37
Fang J X, You H J, Kong P, et al. Dendritic silver nanostructure growth and evolution in replacement reaction. Cryst Growth Des, 2007, 7: 864–867
Tian Z R, Liu J, Voigt J A, et al. Dendritic growth of cubically ordered nanoporous materials through self-assembly. Nano Lett, 2003, 3: 89–92
Lipton J, Glicksman M E, Kurz W. Dendritic growth into undercooled alloy metals. Mater Sci Eng, 1984, 65: 57–63
Lipton J, Kurz W, Trivedi R. Rapid dendrite growth in undercooled alloys. Acta Metall, 1987, 35: 957–964
Lipton J, Kurz W, Trivedi R. Effect of growth rate dependent partition coefficient on the dendritic growth in undercooled Melts. Acta Metall, 1987, 35: 965–970
Galenko P K, Sobolev S. Local nonequilibrium effect on undercooling in rapid solidification of alloys. Phys Rev E, 1997, 55: 343–352
Ando T, Önel S. Comparison and extension of free dendritic growth models through application to a Ag-15 mass Pct Cu alloy. Metall Mat Trans A, 2008, 39: 2449–2458
Arnold C B, Aziz M J, Schwarz M, et al. Parameter-free test of alloy dendrite-growth theory. Phys Rev B, 1999, 59: 334–343
Boettinger W J, Coriell S R, Trivedi R. Rapid Solidification Processing-Principles and Technologies. Mehrabian R, Parrish P A, eds. Baton Rouge, La: Claitor, 1988. 13–15
Boettinger W J, Warren J A, Beckermann C, et al. Phase-field simulation of solidification. Ann Rev Mater Res, 2002, 32: 163–194
Ramirez J C, Beckermann C. Examination of binary alloy free dendritic growth theories with a phase-field model. Acta Mater, 2005, 53: 1721–1736
Guerdane M, Wendler F, Danilov D, et al. Crystal growth and melting in NiZr alloy: Linking phase-field modeling to molecular dynamics simulations. Phys Rev B, 2010, 81: 224108
Becker C A, Olmsted D, Asta M, et al. Atomistic underpinnings for orientation selection in alloy dendritic growth. Phys Rev Lett, 2007, 98: 125701
LaCombe J C, Koss M B, Glicksman M E. Nonconstant Tip velocity in microgravity dendritic growth. Phys Rev Lett, 1999, 83: 2997–3000
Kertz J E, Matson D. Measurement of steel growth kinetics using TEMPUS aboard the NASA KC-135 parabolic aircraft, microgravity research and aplications in physical sciences and biotechnology. Proceedings of the First International Symposium, Sep. 10–15, 2000, Sorrento, Italy. Minster O, Schürmann B, eds. European Space Agency, ESA SP-454, 2001. 639–646
Kolbe M, Cao C D, Lu X Y, et al. Solidification behaviour of undercooled Co-Cu alloys showing a metastable miscibility gap. Mater Sci Eng A, 2004, 375–377: 520–523
Song X Z, Wang H P, Ruan Y, et al. Rapid dendrite growth in quaternary Ni-based alloys. Chin Sci Bull, 2006, 51: 897–901
Eckler K, Cochrane R F, Herlach D M, et al. Evidence for a transition from diffusion-controlled to thermally controlled solidification in metallic alloys. Phys Rev B, 1992, 45: 5019–5022
Wang W L, Shen C L, Luo B C, et al. Sluggish dendrite growth in substantially undercooled liquid Fe-Sb alloy. Philos Mag Lett, 2009, 89: 409–418
Cao C D, Görler G P, Herlach D M, et al. Liquid-liquid phase separation in undercooled Co-Cu alloys. Mater Sci Eng A, 2002, 325: 503–510
Aziz M J. Model for solute redistribution during rapid solidification. J Appl Phys, 1982, 53: 1158–1168
Aziz M J, Tsao J Y, Thompson M O, et al. Solute trapping: Comparison of theory with experiment. Phys Rev Lett, 1986, 56: 2489–2492
Cao C D, Letzig T, Görler G P, et al. Liquid phase separation in undercooled Co-Cu alloys processed by electromagnetic levitation and differential thermal analysis. J Alloys Compd, 2001, 325: 113–117
Cao C D, Lu X Y, Wei B. Solute diffusion controlled dendritic growth under high undercooling conditions. Chin Phys Lett, 1998, 15: 840–842