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Volume-averaged modeling of multiphase solidification with equiaxed crystal sedimentation in a steel ingot 被引量:1
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作者 Xiao-lei Zhu Shuang Cao +5 位作者 Rui Guan Ji Yang Zhe Ning Xin-gang Ai Sheng-li Li Xin-cheng Miao 《China Foundry》 SCIE EI CAS CSCD 2024年第3期229-238,共10页
Macrosegregation is a critical factor that limits the mechanical properties of materials.The impact of equiaxed crystal sedimentation on macrosegregation has been extensively studied,as it plays a significant role in ... Macrosegregation is a critical factor that limits the mechanical properties of materials.The impact of equiaxed crystal sedimentation on macrosegregation has been extensively studied,as it plays a significant role in determining the distribution of alloying elements and impurities within a material.To improve macrosegregation in steel connecting shafts,a multiphase solidification model that couples melt flow,heat transfer,microstructure evolution,and solute transport was established based on the volume-averaged Eulerian-Eulerian approach.In this model,the effects of liquid phase,equiaxed crystals,columnar dendrites,and columnar-to-equiaxed transition(CET)during solidification and evolution of microstructure can be considered simultaneously.The sedimentation of equiaxed crystals contributes to negative macrosegregation,where regions between columnar dendrites and equiaxed crystals undergo significant A-type positive macrosegregation due to the CET.Additionally,noticeable positive macrosegregation occurs in the area of final solidification in the ingot.The improvement in macrosegregation is beneficial for enhancing the mechanical properties of connecting shafts.To mitigate the thermal convection of molten steel resulting from excessive superheating,reducing the superheating during casting without employing external fields or altering the design of the ingot mold is indeed an effective approach to control macrosegregation. 展开更多
关键词 ingot casting multiphase solidification model equiaxed crystal sedimentation microstructure MACROSEGREGATION
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Exploration of the coupled lattice Boltzmann model based on a multiphase field model:A study of the solid-liquid-gas interaction mechanism in the solidification process
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作者 朱昶胜 王利军 +2 位作者 高梓豪 刘硕 李广召 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期638-648,共11页
A multiphase field model coupled with a lattice Boltzmann(PF-LBM)model is proposed to simulate the distribution mechanism of bubbles and solutes at the solid-liquid interface,the interaction between dendrites and bubb... A multiphase field model coupled with a lattice Boltzmann(PF-LBM)model is proposed to simulate the distribution mechanism of bubbles and solutes at the solid-liquid interface,the interaction between dendrites and bubbles,and the effects of different temperatures,anisotropic strengths and tilting angles on the solidified organization of the SCN-0.24wt.%butanedinitrile alloy during the solidification process.The model adopts a multiphase field model to simulate the growth of dendrites,calculates the growth motions of dendrites based on the interfacial solute equilibrium;and adopts a lattice Boltzmann model(LBM)based on the Shan-Chen multiphase flow to simulate the growth and motions of bubbles in the liquid phase,which includes the interaction between solid-liquid-gas phases.The simulation results show that during the directional growth of columnar dendrites,bubbles first precipitate out slowly at the very bottom of the dendrites,and then rise up due to the different solid-liquid densities and pressure differences.The bubbles will interact with the dendrite in the process of flow migration,such as extrusion,overflow,fusion and disappearance.In the case of wide gaps in the dendrite channels,bubbles will fuse to form larger irregular bubbles,and in the case of dense channels,bubbles will deform due to the extrusion of dendrites.In the simulated region,as the dendrites converge and diverge,the bubbles precipitate out of the dendrites by compression and diffusion,which also causes physical phenomena such as fusion and spillage of the bubbles.These results reveal the physical mechanisms of bubble nucleation,growth and kinematic evolution during solidification and interaction with dendrite growth. 展开更多
关键词 multiphase field model lattice Boltzmann model(LBM) Shan-Chen multiphase flow solidification organization
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Recent research progress on the phase-field model of microstructural evolution during metal solidification 被引量:3
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作者 Kaiyang Wang Shaojie Lv +6 位作者 Honghui Wu Guilin Wu Shuize Wang Junheng Gao Jiaming Zhu Xusheng Yang Xinping Mao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第11期2095-2111,共17页
Solidification structure is a key aspect for understanding the mechanical performance of metal alloys,wherein composition and casting parameters considerably influence solidification and determine the unique microstru... Solidification structure is a key aspect for understanding the mechanical performance of metal alloys,wherein composition and casting parameters considerably influence solidification and determine the unique microstructure of the alloys.By following the principle of free energy minimization,the phase-field method eliminates the need for tracking the solid/liquid phase interface and has greatly accelerated the research and development efforts geared toward optimizing metal solidification microstructures.The recent progress in the application of phasefield simulation to investigate the effect of alloy composition and casting process parameters on the solidification structure of metals is summarized in this review.The effects of several typical elements and process parameters,including carbon,boron,silicon,cooling rate,pulling speed,scanning speed,anisotropy,and gravity,on the solidification structure are discussed.The present work also addresses the future prospects of phase-field simulation and aims to facilitate the widespread applications of phase-field approaches in the simulation of microstructures during solidification. 展开更多
关键词 solidification process phase-field models microstructure evolution alloy composition casting process parameters
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Comparative analysis of isothermal and non-isothermal solidification of binary alloys using phase-field model 被引量:2
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作者 肖荣振 安国升 +2 位作者 朱昶胜 王智平 杨世银 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第11期3639-3644,共6页
Based on the entropy function, a two-dimensional phase field model of binary alloys was established. Meanwhile, an explicit difference method with uniform grid was adopted to solve the phase field and solute field con... Based on the entropy function, a two-dimensional phase field model of binary alloys was established. Meanwhile, an explicit difference method with uniform grid was adopted to solve the phase field and solute field controlled equations. And the alternating direction implicit(ADI) algorithm for solving temperature field controlled equation was also employed to avoid the restriction of time step. Some characteristics of the Ni-Cu alloy were captured in the process of non-isothermal solidification, and the comparative analysis of the isothermal and the non-isothermal solidification was investigated. The simulation results indicate that the non-isothermal model is favorable to simulate the real solidification process of binary alloys, and when the thermal diffusivity decreases, the non-isothermal phase-field model is gradually consistent with the isothermal phase-field model. 展开更多
关键词 phase-field model binary alloys isothermal solidification non-isothermal solidification
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Fluid Flow and Solidification Simulation in Beam Blank Continuous Casting Process With 3D Coupled Model 被引量:14
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作者 YANG Jian-wei DU Yan-ping +1 位作者 SHI Rong CUI Xiao-chao 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2006年第4期17-21,共5页
Based on turbulent theory, a 3D coupled model of fluid flow and solidification was built using finite difference method and used to study the influence of superheating degree and casting speed on fluid flow and solidi... Based on turbulent theory, a 3D coupled model of fluid flow and solidification was built using finite difference method and used to study the influence of superheating degree and casting speed on fluid flow and solidification, analyze the interaction between shell and molten steel, and compare the temperature distribution under different technological conditions. The results indicate that high superheating degree can lengthen the liquid-core depth and make the crack and breakout possible, so suitable superheating should be controlled within 35℃ according to the simulation results. Casting speed which is one of the most important technological parameters of improving production rate, should be controlled between 0. 85 m/min and 1.05 m/min and the caster has great potential in the improvement of blank quality. 展开更多
关键词 beam blank continuous casting flow field temperature distribution coupled model solidification
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A coupled model of TiN inclusion growth in GCr15SiMn during solidification in the electroslag remelting process 被引量:5
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作者 Liang Yang Guo-guang Cheng +3 位作者 Shi-jian Li Min Zhao Gui-ping Feng Tao Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2015年第12期1266-1272,共7页
TiN inclusions observed in an ingot produced by electroslag remelting (ESR) are extremely harmful to GCrl5SiMn steel. Therefore, accurate predictions of the growth size of these inclusions during steel solidificatio... TiN inclusions observed in an ingot produced by electroslag remelting (ESR) are extremely harmful to GCrl5SiMn steel. Therefore, accurate predictions of the growth size of these inclusions during steel solidification are significant for clean ESR ingot production. On the basis of our previous work, a coupled model of solute microsegregation and TiN inclusion growth during solidification has been established. The results demonstrate that compared to a non-coupled model, the coupled model predictions of the size of TiN inclusions are in good agreement with experimental results using scanning electron microscopy with energy disperse spectroscopy (SEM-EDS). Because of high cooling rate, the sizes of TiN inclusions in the edge area of the ingots are relatively small compared to the sizes in the center area. During the ESR process, controlling the content of Ti in the steel is a feasible and effective method of decreasing the sizes of TiN inclusions. 展开更多
关键词 coupled model solidification INCLUSIONS bearing steel electroslag remelting
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Progress on modeling and simulation of directional solidification of superalloy turbine blade casting 被引量:6
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作者 Xu Qingyan Liu Baicheng +1 位作者 Pan Dong Yu Jing 《China Foundry》 SCIE CAS 2012年第1期69-77,共9页
Directional solidified turbine blades of Ni-based superalloy are widely used as key parts of the gas turbine engines.The mechanical properties of the blade are greatly influenced by the final microstructure and the gr... Directional solidified turbine blades of Ni-based superalloy are widely used as key parts of the gas turbine engines.The mechanical properties of the blade are greatly influenced by the final microstructure and the grain orientation determined directly by the grain selector geometry of the casting.In this paper,mathematical models were proposed for three dimensional simulation of the grain growth and microstructure evolution in directional solidification of turbine blade casting.Ray-tracing method was applied to calculate the temperature variation of the blade.Based on the thermo model of heat transfer,the competitive grain growth within the starter block and the spiral of the grain selector,the grain growth in the blade and the microstructure evolution were simulated via a modified Cellular Automaton method.Validation experiments were carried out,and the measured results were compared quantitatively with the predicted results.The simulated cooling curves and microstructures corresponded well with the experimental results.The proposed models could be used to predict the grain morphology and the competitive grain evolution during directional solidification. 展开更多
关键词 Ni-based superalloy MICROSTRUCTURE directional solidification modelING
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Numerical simulation of solidification morphologies of Cu-0.6Cr casting alloy using modified cellular automaton model 被引量:9
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作者 TSAI De-chang HWANG Weng-sing 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第6期1072-1077,共6页
The purpose of this study is to predict the morphologies in the solidification process for Cu-0.6Cr(mass fraction,%)alloy by vacuum continuous casting(VCC)and verify its accuracy by the observed experimental results.I... The purpose of this study is to predict the morphologies in the solidification process for Cu-0.6Cr(mass fraction,%)alloy by vacuum continuous casting(VCC)and verify its accuracy by the observed experimental results.In numerical simulation aspect, finite difference(FD)method and modified cellular automaton(MCA)model were used to simulate the macro-temperature field, micro-concentration field,nucleation and grain growth of Cu-0.6Cr alloy using real data from actual casting operations.From the observed casting experiment,the preliminary grain morphologies are the directional columnar grains by the VCC process.The solidification morphologies by MCAFD model are in agreement with the result of actual casting experiment well. 展开更多
关键词 Cu-Cr alloy vacuum continuous casting solidification morphology simulation modified cellular automaton model finite difference method
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Numerical Evaluation of Two k-εTurbulence Model for Predicting Flow and Solidification in Continuous Casting Slab 被引量:2
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作者 LIU He-ping GAN Yong QIU Sheng-tao 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2003年第2期10-16,共7页
A steady three-dimensional fluid flow and solidification model was built based on CFD software by high-Reynolds-number and Lam-Bremhorst low-Reynolds-number k-ε model.During the simulation,the fixed-grid enthalpy-por... A steady three-dimensional fluid flow and solidification model was built based on CFD software by high-Reynolds-number and Lam-Bremhorst low-Reynolds-number k-ε model.During the simulation,the fixed-grid enthalpy-porosity technique was used to represent the solidification,and Darcy law was adopted to simulate the flow in mushy region.The prediction for steel flow and solidification was evaluated by the comparison of two turbulence models.It is found that both Lam-Bremhorst low-Reynolds-number and high-Reynolds-number k-ε models predict the same trend of the steel flow and temperature distribution.However,due to the effect of turbulent flow on heat transfer,the low-Reynolds-number turbulence model predicts longer penetration depth of molten steel in sub-mold region,less shell growth and higher shell surface temperature at the narrow face compared with standard k-ε model. 展开更多
关键词 continuous slab caster solidification steel flow turbulence model numerical simulation
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Phase field modeling of multiple dendrite growth of Al-Si binary alloy under isothermal solidification 被引量:6
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作者 Sun Qiang Zhang Yutuo +1 位作者 Cui Haixia Wang Chengzhi 《China Foundry》 SCIE CAS 2008年第4期265-267,共3页
Phase field method offers the prospect of being able to perform realistic numerical experiments on dendrite growth in metallic systems. In this study, the growth process of multiple dendrites in AI-2-mole-%-Si binary ... Phase field method offers the prospect of being able to perform realistic numerical experiments on dendrite growth in metallic systems. In this study, the growth process of multiple dendrites in AI-2-mole-%-Si binary alloy under isothermal solidification was simulated using phase field model. The simulation results showed the impingement of arbitrarily oriented crystals and the competitive growth among the grains during solidification. With the increase of growing time, the grains begin to coalesce and impinge the adjacent grains. When the dendrites start to impinge, the dendrite growth is obviously inhibited. 展开更多
关键词 phase field model multiple dendrite growth binary alloy isothermal solidification
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Multiscale modelling and simulation of single crystal superalloy turbine blade casting during directional solidification process 被引量:2
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作者 Xu Qingyan Zhang Hang Liu Baicheng 《China Foundry》 SCIE CAS 2014年第4期268-276,共9页
As the key parts of an aero-engine,single crystal(SX)superalloy turbine blades have been the focus of much attention.However,casting defects often occur during the manufacturing process of the SX turbine blades.Modeli... As the key parts of an aero-engine,single crystal(SX)superalloy turbine blades have been the focus of much attention.However,casting defects often occur during the manufacturing process of the SX turbine blades.Modeling and simulation technology can help to optimize the manufacturing process of SX blades.Multiscale coupled models were proposed and used to simulate the physical phenomena occurring during the directional solidification(DS)process.Coupled with heat transfer(macroscale)and grain growth(meso-scale),3D dendritic grain growth was calculated to show the competitive grain growth at micro-scale.SX grain selection behavior was studied by the simulation and experiments.The results show that the geometrical structure and technical parameters had strong influences on the grain selection effectiveness.Based on the coupled models,heat transfer,grain growth and microstructure evolution of a complex hollow SX blade were simulated.Both the simulated and experimental results show that the stray grain occurred at the platform of the SX blade when a constant withdrawal rate was used in manufacturing process.In order to avoid the formation of the stray crystal,the multi-scale coupled models and the withdrawal rate optimized technique were applied to the same SX turbine blade.The modeling results indicated that the optimized variable withdrawal rate can achieve SX blade castings with no stray grains,which was also proved by the experiments. 展开更多
关键词 directional solidification single crystal superalloy turbine blade casting grain selection modeling and simulation
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Metallurgical modeling of microcrack repairment during welding nonferrous materials: non-equilibrium solidification behavior of weld pool (Ⅰ) 被引量:2
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作者 Gao Zhiguo 《China Welding》 EI CAS 2017年第2期32-42,共11页
Metallurgical modeling of synergistic microcrack self-repairmen during welding single crystal and polycrystalline superalloys of high-temperature aerospace materials has been properly established. The idea of improvem... Metallurgical modeling of synergistic microcrack self-repairmen during welding single crystal and polycrystalline superalloys of high-temperature aerospace materials has been properly established. The idea of improvement of nickel-based superalloys weldability through non-equilibrium solidification behavior of backfill to self-repair arterial crack network is usefully proposed. Crystallographic control strategy of crack self-repairmen of fusion zone interdendritic solidification cracking and heat-affected zone (HAZ) intergranular liquation cracking is technically achievable, indicating that optimal niobium alloying beneficially refines weld microstructure, stabilizes the primary solidification path, increases the solidification temperature and concomitantly decreases the weld pool geometry. High-carbon grain boundary is more thermal stable and less contributes to incipient intergranular liquid film than that of low-carbon grain boundary. The theoretical predictions of cracking susceptibility are indirectly verified in a rather satisfactory manner. Additionally, the metallurgical modeling enhances predicative capabilities and thereby is readily applicable for other alloy systems. 展开更多
关键词 metallurgical modeling nickel alloys solidification behavior cracking repairmen
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On establishment of novel constitutive model for directionally solidified nickel-based superalloys utilizing machine learning methods
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作者 Jia-yan Sun Rong Yin +2 位作者 Ye-yuan Hu Yun-xiang Tan Qing-yan Xu 《China Foundry》 SCIE CAS CSCD 2023年第5期365-375,共11页
To enhance the accuracy of mechanical simulation in the directional solidification process of turbine blades for heavy-duty gas turbines,a new constitutive model that employs machine learning methods was developed.Thi... To enhance the accuracy of mechanical simulation in the directional solidification process of turbine blades for heavy-duty gas turbines,a new constitutive model that employs machine learning methods was developed.This model incorporates incremental learning and transfer learning,thus improves the predictive accuracy and generalization performance.To account for the anisotropy of the directionally solidified alloy,a deformation direction parameter is added to the model,enabling prediction of the stress-strain relationship of the alloy under different deformation directions.The predictive capabilities of both models are evaluated using correlation coefficient(R),average relative error(δ),and value of relative error(RE).Compared to the traditional model,the machine learning constitutive model achieves higher prediction accuracy and better generalization performance.This offers a new approach for the establishment of flow constitutive models for other directionally solidified and single-crystal superalloys. 展开更多
关键词 Ni-based superalloy constitutive model machine learning directional solidification ANISOTROPY
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Simulation and control model for interactions among process parameters of directional solidification continuous casting 被引量:1
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作者 彭立明 毛协民 徐匡迪 《中国有色金属学会会刊:英文版》 EI CSCD 2000年第4期449-452,共4页
On the basis of analyzing the principles, equipment and control needs of directional solidification continuous casting (DSCC) process, the building and fulfilling methods of control model of DSCC procedure by neural n... On the basis of analyzing the principles, equipment and control needs of directional solidification continuous casting (DSCC) process, the building and fulfilling methods of control model of DSCC procedure by neural network control (NNC) method were proposed and discussed. Combining the experimental researches, firstly the computer is used to simulate the effects of those solidification parameters on destination control variable (S/L interface) and the reactions among those parameters during DSCC procedure; secondly many training samples can be obtained. Moreover, after these samples are input into neural network software (NNs) and trained, the control model can be built. 展开更多
关键词 directional solidification continuous CASTING control model
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Prediction of mushy zone permeability of Al-4.5wt%Cu alloy during solidification by phase field model and CFD simulation 被引量:1
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作者 Long-fei Li Rui-jie Zhang +4 位作者 Shi-jie Hu Dan Zhang Shi-di Yang Chang-sheng Wang Hai-tao Jiang 《China Foundry》 SCIE 2019年第5期313-318,共6页
Liquid permeability of the mushy zone is important for porosity formation during the solidification process. In order to investigate the permeability of the mushy zone, an integrated model was developed by combining t... Liquid permeability of the mushy zone is important for porosity formation during the solidification process. In order to investigate the permeability of the mushy zone, an integrated model was developed by combining the phase field model and computational fluid dynamics (CFD) model. The three-dimensional multigrain dendrite morphology was obtained by using the phase field model. Subsequently, the computer-aided design (CAD) geometry and mesh were generated based on calculated dendrite morphologies. Finally, the permeability of the dendritic mushy zone was obtained by solving the Navier-Stokes and continuity equations in ANSYS Fluent software. As an example, the dendritic mushy zone permeability of Al-4.5wt%Cu alloy and its relationship with the solid fractions were studied in detail. The predicted permeability data can be input to the solidification model on a greater length scale for macro segregation and porosity simulations. 展开更多
关键词 phase field model mushy ZONE COMPUTATIONAL FLUID dynamics PERMEABILITY solidification
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Interface kinetics modeling of binary alloy solidification by considering correlation between thermodynamics and kinetics 被引量:2
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作者 Shu LI Yu-bing ZHANG +1 位作者 Kang WANG Feng LIU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第1期306-316,共11页
By considering collision-limited growth mode and short-range diffusion-limited growth mode simultaneously,an extended kinetic model for solid−liquid interface with varied kinetic prefactor was developed for binary all... By considering collision-limited growth mode and short-range diffusion-limited growth mode simultaneously,an extended kinetic model for solid−liquid interface with varied kinetic prefactor was developed for binary alloys.Four potential correlations arising from effective kinetics coupling the two growth modes were proposed and studied by application to planar interface migration and dendritic solidification,where the linear correlation between the effective thermodynamic driving force and the effective kinetic energy barrier seems physically realistic.A better agreement between the results of free dendritic growth model and the available experiment data for Ni−0.7at.%B alloy was obtained based on correlation between the thermodynamics and kinetics.As compared to previous models assuming constant kinetic prefactor,a common phenomenon occurring at relatively low undercoolings,i.e.the interface migration slowdown,can be ascribed to both the thermodynamic and the kinetic factors.By considering universality of the correlation between the thermodynamics and kinetics,it is concluded that the correlation should be considered to model the interface kinetics in alloy solidification. 展开更多
关键词 modelling INTERFACE dendritic solidification binary alloy THERMODYNAMICS KINETICS CORRELATION
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Modeling of microporosity formation and hydrogen concentration evolution during solidification of an Al-Si alloy 被引量:2
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作者 Qingyu Zhang Dongke Sun +2 位作者 Shunhu Zhang Hui Wang Mingfang Zhu 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第7期567-575,共9页
We simulate the evolution of hydrogen concentration and gas pore formation as equiaxed dendrites grow during solidification of a hypoeutectic aluminum-silicon(Al-Si)alloy.The applied lattice Boltzmann-cellular automat... We simulate the evolution of hydrogen concentration and gas pore formation as equiaxed dendrites grow during solidification of a hypoeutectic aluminum-silicon(Al-Si)alloy.The applied lattice Boltzmann-cellular automaton-finite difference model incorporates the physical mechanisms of solute and hydrogen partitioning on the solid/liquid interface,as well as the transports of solute and hydrogen.After the quantitative validation by the simulation of capillary intrusion,the model is utilized to investigate the growth of the equiaxed dendrites and hydrogen porosity formation for an Al-(5 wt.%)Si alloy under different solidification conditions.The simulation data reveal that the gas pores favorably nucleate in the corners surrounded by the nearby dendrite arms.Then,the gas pores grow in a competitive mode.With the cooling rate increasing,the competition among different growing gas pores is found to be hindered,which accordingly increases the pore number density in the final solidification microstructure.In the late solidification stage,even though the solid fraction is increasing,the mean concentration of hydrogen in the residue melt tends to be constant,corresponding to a dynamic equilibrium state of hydrogen concentration in liquid.As the cooling rate increases or the initial hydrogen concentration decreases,the temperature of gas pore nucleation,the porosity fraction,and the mean porosity size decrease,whilst the mean hydrogen concentration in liquid increases in the late solidification stage.The simulated data present identical trends with the experimental results reported in literature. 展开更多
关键词 MICROPOROSITY solidification microstructure modeling lattice Boltzmann method
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A coupled model on fluid flow,heat transfer and solidification in continuous casting mold 被引量:2
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作者 Xu-bin Zhang Wei Chen Li-feng Zhang 《China Foundry》 SCIE 2017年第5期416-420,共5页
Fluid flow, heat transfer and solidification of steel in the mold are so complex but crucial, determining the surface quality of the continuous casting slab. In the current study, a 2D numerical model was established ... Fluid flow, heat transfer and solidification of steel in the mold are so complex but crucial, determining the surface quality of the continuous casting slab. In the current study, a 2D numerical model was established by Fluent software to simulate the fluid flow, heat transfer and solidification of the steel in the mold. The VOF model and k-ε model were applied to simulate the flow field of the three phases(steel, slag and air), and solidification model was used to simulate the solidification process. The phenomena at the meniscus were also explored through interfacial tension between the liquid steel and slag as well as the mold oscillation. The model included a 20 mm thick mold to clarify the heat transfer and the temperature distribution of the mold. The simulation results show that the liquid steel flows as upper backflow and lower backflow in the mold, and that a small circulation forms at the meniscus. The liquid slag flows away from the corner at the meniscus or infiltrates into the gap between the mold and the shell with the mold oscillating at the negative strip stage or at the positive strip stage. The simulated pitch and the depth of oscillation marks approximate to the theoretical pitch and measured depth on the slab. 展开更多
关键词 continuous casting heat transfer solidification VOF model meniscus shape MOLD
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Modelling and Simulation of Solidification Phenomena during Additive Manufacturing of Bulk Metallic Glass Matrix Composites (BMGMC)—A Brief Review and Introduction of Technique 被引量:2
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作者 Muhammad Musaddique Ali Rafique 《Journal of Encapsulation and Adsorption Sciences》 2018年第2期67-116,共50页
Despite a wealth of experimental studies focused on determining and improving mechanical properties and development of fundamental understanding of underlying mechanisms behind nucleation and growth of ductile phase p... Despite a wealth of experimental studies focused on determining and improving mechanical properties and development of fundamental understanding of underlying mechanisms behind nucleation and growth of ductile phase precipitates from melt in glassy matrix, still, there is dearth of knowledge about how these ductile phases nucleate during solidification. Various efforts have been made to address this problem such as experiments in microgravity, high resolution electron microscopy and observation in synchrotron light after levitation but none have proved out to be satisfactory. In this study, an effort has been made to address this problem by modelling and simulation. Current state of the art of development, manufacturing, characterisation and modelling and simulation of bulk metallic glass matrix composites is described in detail. Evolution of microstructure in bulk metallic glass matrix composites during solidification in additive manufacturing has been presented with the aim to address fundamental problem of evolution of solidification microstructure as a result of solute partitioning, diffusion and capillary action. An overview is also presented to explain the relation of microstructure evolution to hardness and fracture toughness. This is aimed at overcoming fundamental problem of lack of ductility and toughness in this diverse class of materials. Quantitative prediction of solidification microstructure is done with the help of advanced part scale modelling and simulation techniques. It has been systematically proposed that 2-dimensional cellular automaton (CA) method combined with finite element (for thermal modelling) tools (CA-FE) programmed on FORTRAN? and parallel simulated on ABAQUS? would best be able to describe this complicated multiphysics phenomenon in most efficient way. Focus is laid on quantification of methodology by which modelling and simulation can be adopted and applied to describe evolution of microstructure in this important class of materials. It is found that proposed methodology is meritorious. 展开更多
关键词 solidification modelling and Simulation CELLULAR AUTOMATON
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Quantitative multi-phase-field modeling of non-isothermal solidification in hexagonal multicomponent alloys 被引量:1
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作者 Yong-biao Wang Ming-guang Wei +5 位作者 Xin-tian Liu Cong Chen Jian-xiu Liu Yu-juan Wu Shuai Dong Li-ming Peng 《China Foundry》 SCIE CAS 2022年第3期263-274,共12页
A quantitative multi-phase-field model for non-isothermal and polycrystalline solidification was developed and applied to dilute multicomponent alloys with hexagonal close-packed structures.The effects of Lewis coeffi... A quantitative multi-phase-field model for non-isothermal and polycrystalline solidification was developed and applied to dilute multicomponent alloys with hexagonal close-packed structures.The effects of Lewis coefficient and undercooling on dendrite growth were investigated systematically.Results show that large Lewis coefficients facilitate the release of the latent heat,which can accelerate the dendrite growth while suppress the dendrite tip radius.The greater the initial undercooling,the stronger the driving force for dendrite growth,the faster the growth rate of dendrites,the higher the solid fraction,and the more serious the solute microsegregation.The simulated dendrite growth dynamics are consistent with predictions from the phenomenological theory but significantly deviate from the classical JMAK theory which neglects the soft collision effect and mutual blocking among dendrites.Finally,taking the Mg-6Gd-2Zn(wt.%)alloy as an example,the simulated dendrite morphology shows good agreement with experimental results. 展开更多
关键词 multi-phase-field model non-isothermal solidification POLYCRYSTALLINE multicomponent alloys dendrite growth microstructure
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