The deflection of columnar grains grown under melt flow is characteristic of the alloy solidification structure and strongly influences the performance of products. Here, a model of grain growth in melt flow was established with the cellular automaton (CA) method. After validation by comparison to an analytical model, the model was used to investigate the deflection of columnar grains in high-carbon steel. The deflection angle of columnar grains increases with the flow velocity and decreases with the melt undercooling. At the flow velocity of 0.10 m s–1 and the melt undercooling of 2°C, a maximum deflection angle of 18.2° is achieved. The deflection angles predicted by the model agree well with the empirical values. The melt flow was found to promote the grains with a preferred growth orientation towards the upstream direction over others. This flow-influenced selection mechanism is a key reason for the deflection of columnar grains.
Get full access to this article
View all access options for this article.
References
1.
FlemingsMCAdamsCHuckeEet al.Metal solidification in a flowing stream. Trans AFS. 1956;64:636–639.
2.
MikschE.Solidification of ice dendrite in flowing supercooled water. Trans Metall Soc AIME. 1969;245(9):2069–2072.
3.
DingZYHuQDZengLet al.Hot deformation characteristics of as-cast high-Cr ultra-super-critical rotor steel with columnar grains. Int J Miner Metall Mater. 2016;23(11):1275–1285.
4.
AbeHToganoK.Study on the textures of Al-Cu alloy ingots solidified from the flowing liquids. J Jpn Inst Met. 1969;33(8):970–975.
5.
AbeHToganoK.Texture of Zn-Cd alloy ingot solidified from the flowing liquid. J Jpn Inst Met. 1970;34(10):993–996.
6.
AbeHToganoK.Continuous observation on dendritic growth of cyclohexanol crystals from the stagnant or flowing liquid. J Jap Inst Met. 1971;35(10):947–951.
7.
OkamotoTKishitakeKBesshoI.Dendritic structure in unidirectionally solidified cyclohexanol. J Cryst Growth. 1975;29(2):131.
8.
DengXXJiCXDongWLet al.Distribution of macro-inclusions in low carbon aluminium-killed steel slabs. Ironmak Steelmak. 2017;49(7):592–602.
9.
TakahashiTIchikawaKKudouMet al.The effect of fluid flow on the macrosegregation in steel ingot. Tetsu To Hagane. 1975;61(9):2198–2213.
10.
OkanoSNishimuraTOoiHet al.Relation between large inclusions and growth directions of columnar dendrites in continuously cast slabs. Tetsu To Hagane. 1975;61(14):2982–2990.
11.
EsakaHSuterFOgibayashiS.Influence of carbon content on the growth angle of steel dendrites in a flowing melt. ISIJ Int. 1996;36(10):1264–1272.
12.
MurakamiKAiharaHOkamotoT.Growth direction of columnar crystals solidified in flowing melt. Acta Metall. 1984;32(6):933–939.
13.
LeeSYLeeSMHongCP.Numerical modeling of deflected columnar dendritic grains solidified in a flowing melt and its experimental verification. ISIJ Int. 2000;40(1):48–57.
14.
TurchinANEskinDGKatgermanL.Effect of melt flow on macro- and microstructure evolution during solidification of an Al-4.5% Cu alloy. Mater Sci Eng A. 2005;413-414:98–104.
15.
WuHJWeiNBaoYPet al.Effect of M-EMS on the solidification structure of a steel billet. Int J Miner Metall Mater. 2011;18(2):159–164.
16.
RenBZChenDFWangHDet al.Numerical simulation of fluid flow and solidification in bloom continuous casting mould with electromagnetic stirring. Ironmak Steelmak. 2014;42(6):401–408.
17.
WangXWangSZhangLet al.Analysis on the deflection angle of columnar dendrites of continuous casting steel billets under the influence of mold electromagnetic stirring. Metall Mater Trans A. 2016;47(11):5496–5509.
18.
EsakaHTaenakaTOhishiHet al.Deflection mechanism of columnar dendrite due to fluid flow. J Jpn Soc Microgravity Appl.1989;6:20–25.
19.
NatsumeYOhsasaKNaritaT.Investigation of the mechanism of alloy dendrite deflection due to flowing melt by phase-field simulation. Mater Trans. 2002;43(9):2228–2234.
20.
GandinCARappazM.A 3D cellular automaton algorithm for the prediction of dendritic grain growth. Acta Mater. 1997;45(5):2187–2195.
21.
LiptonJGlicksmanMEKurzW.Dendritic growth into undercooled alloy metals. Mater Sci Eng. 1984;65(1):57–63.
22.
RappazMGandinCA.Probabilistic modelling of microstructure formation in solidification processes. Acta Metall Mater. 1993;41(2):345–360.
23.
GandinCAGuillemotGAppolaireBet al.Boundary layer correlation for dendrite tip growth with fluid flow. Mater Sci Eng A. 2003;342(1):44–50.
24.
KurzWFisherDJ.Dendrite growth at the limit of stability: tip radius and spacing. Acta Metall. 1981;29(1):11–20.
25.
WangJWangFLiCet al.Simulation of 3D-microstructure in free-cutting steel 9SMn28 under water cooling condition with convection and porosity. ISIJ Int. 2010;50(2):222–230.
26.
LuoSZhuMLouhenkilpiS.Numerical simulation of solidification structure of high carbon steel in continuous casting using cellular automaton method. ISIJ Int. 2012;52(5):823–663.
27.
ZhuMFLeeSYHongCP.Modified cellular automaton model for the prediction of dendritic growth with melt convection. Phys Rev E. 2004;69(6):061610.
28.
LuoSWangWZhuM.Validation and simulation of cellular automaton model for dendritic growth during the solidification of Fe-C binary alloy with fluid flow. ISIJ Int. 2016;56(4):564–573.
29.
WangWLuoSZhuM.Dendritic growth of high carbon iron-based alloy under constrained melt flow. Comput Mater Sci. 2014;95:136–148.
30.
AnanthRGillWN.Self-consistent theory of dendritic growth with convection. J Cryst Growth. 1991;108(1):173–189.
