Herlach / Matson Solidification of Containerless Undercooled Melts

1. Auflage 2012
ISBN: 978-3-527-64792-7
Verlag: Wiley-VCH
Format: EPUB
Kopierschutz: Adobe DRM (»Systemvoraussetzungen)

E-Book, Englisch, 554 Seiten, E-Book

All metallic materials are prepared from the liquid state as their parent phase. Solidification is therefore one of the most important phase transformation in daily human life. Solidification is the transition from liquid to solid state of matter. The conditions under which material is transformed determines the physical and chemical properties of the as-solidified body. The processes involved, like nucleation and crystal growth, are governed by heat and mass transport.
Convection and undercooling provide additional processing parameters to tune the solidification process and to control solid material performance from the very beginning of the production chain.
To develop a predictive capability for efficient materials production the processes involved in solidification have to be understood in detail.
This book provides a comprehensive overview of the solidification of metallic melts processed and undercooled in a containerless manner
by drop tube, electromagnetic and electrostatic levitation, and experiments in reduced gravity.
The experiments are accompanied by model calculations on the influence of thermodynamic and hydrodynamic conditions that control
selection of nucleation mechanisms and modify crystal growth development throughout the solidification process.

Autoren/Hrsg.

Herlach, Dieter M.

Matson, Douglas M.

Inhaltsverzeichnis

Containerless undercooling of drops and droplets Computer aided experiments in containerless processing of materials
Demixing of Cu-Co alloys showing a metastable miscibility gap
Short range order in undercooled melts
Influence of order in undercooled liquids on crystal nucleation
Crystal nucleation in undercooled melts
Phase field crystal modelling of homogeneous and heterogeneous crystal nucleation
Effects of transient heat and mass transfer and competitive nucleation on phase selection in rapid solidification
Nucleation of metastable phases in undercooled melts
Nucleation within the mushy-zone
Measurements of crystal growth velocities in undercooled melts of metals
Measurements of crystal growth in undercooled melts of semiconductors
Measurements of crystal growth dynamics in strong external magnetic fields
Influence of convection on dendrite growth dynamics by AC + DC levitation technique
Development of a numerical approach for modelling dendritic growth in EML of liquid metal drops
Mesoscopic modelling of dendrite growth in undercooled melts
Microscopic modelling of growth kinetics in undercooled melts
Multiscale solidification modelling of EML processed samples
Interaction of fine particles with dendrites in undercooled melts of semiconducting materials
Quantitative analysis of alloy structures solidified under limited diffusion conditions

PREFACE
 
CONTAINERLESS UNDERCOOLING OF DROPS AND DROPLETS
Introduction
Drop Tubes
Containerless Processing Through Levitation
Summary and Conclusions
 
COMPUTER-AIDED EXPERIMENTS IN CONTAINERLESS PROCESSING OF MATERIALS
Introduction
Planning Experiments
Operating Experiments
Data Reduction, Analysis, Visualization, and Interpretation
Conclusion
 
DEMIXING OF CU - CO ALLOYS SHOWING A METASTABLE MISCIBILITY GAP
Introduction
Mechanism of Demixing
Demixing Experiments in Terrestrial EML and in Low Gravity
Demixing Experiments in a Drop Tube
Spinodal Decomposition in Cu - Co Melts
Conclusions
 
SHORT-RANGE ORDER IN UNDERCOOLED MELTS
Introduction
Experiments on the Short-Range Order of Undercooled Melts
Conclusions
 
ORDERING AND CRYSTAL NUCLEATION IN UNDERCOOLED MELTS
Introduction
Nucleation Theory - Some Background
Liquid Metal Undercooling Studies
Coupling of Ordering in the Liquid to the Nucleation Barrier
Conclusions
 
PHASE-FIELD CRYSTAL MODELING OF HOMOGENEOUS AND HETEROGENEOUS CRYSTAL NUCLEATION
Introduction
Phase-Field Crystal Models
Homogeneous Nucleation
PFC Modeling of Heterogeneous NuCleation
Summary
 
EFFECTS OF TRANSIENT HEAT AND MASS TRANSFER ON COMPETITIVE NUCLEATION AND PHASE SELECTION IN DROP TUBE PROCESSING OF MULTICOMPONENT ALLOYS
Introduction
Model
Effect of Transient Heat and Mass Transfer on Nucleation and Crystal Growth
Competitive Nucleation and Phase Selection in Nd - Fe - B Droplets
Summary
 
CONTAINERLESS SOLIDIFICATION OF MAGNETIC MATERIALS USING THE ISAS/JAXA 26-METER DROP TUBE
Introduction
Drop Tube Process
Undercooling Solidification of Fe - Rare Earth (RE) Magnetostriction Alloys
Undercooling Solidification of Nd - Fe - B Magnet Alloys
Concluding Remarks
 
NUCLEATION AND SOLIDIFICATION KINETICS OF METASTABLE PHASES IN UNDERCOOLED MELTS
Introduction
Thermodynamic Aspects and Nucleation of Metastable Phases
Metastable Phase Formation from Undercooled Melts in Various Alloy Systems
Summary and Conclusions
 
NUCLEATION WITHIN THE MUSHY ZONE
Introduction
Incubation Time
Cluster Formation
Transient Development of Heterogeneous Sites
Comparing Critical Nucleus Development Mechanisms
Concluding Remarks
 
MEASUREMENTS OF CRYSTAL GROWTH VELOCITIES IN UNDERCOOLED MELTS OF METALS
Introduction
Experimental Methods
Summary and Conclusions
 
CONTAINERLESS CRYSTALLIZATION OF SEMICONDUCTORS
Introduction
Status of Research on Facetted Dendrite Growth
Twin-Related Lateral Growth and Twin-free Continuous Growth
Containerless Crystallization of Si
Summery and Conclusion
Appendix 12.A: LKT Model
 
MEASUREMENTS OF CRYSTAL GROWTH DYNAMICS IN GLASS-FLUXED MELTS
Introduction
Methods and Experimental Set-Up
Growth Velocities in Pure Ni
Growth Velocities in Ni3Sn2 Compound
Crystal Growth Dynamics in Ni - Sn Eutectic Alloys
Opportunities with High Magnetic Fields
Summary
 
INFLUENCE OF CONVECTION ON DENDRITE GROWTH BY THE AC - DC LEVITATION TECHNIQUE
Convection in a Levitated Melt
Static Levitation Using the Alternating and Static Magnetic Field (AC - DC Levitation)
Effect of Convection on Nucleation and Solidification
 
MODELING THE FLUID DYNAMICS AND DENDRITIC SOLIDIFICATION IN EM-LEVITATED ALLOY MELTS 321
Introduction
Mathematical Models for Levitation Thermofluid Dynamics
Thermoelectric Magnetohydrodynamics in Levitated Droplets
Concluding Remarks
 
FORCED FLOW EFFECT ON DENDRITIC GROWTH KINETICS IN A BINARY NONISOTHERMAL SYSTEM
Introduction
Convective Flow in Droplets Processed in Electromagnetic Levitation
The Model Equations
Predictions of the Model
Quantitative Evaluations
Summary and Conclusions
 
ATOMISTIC SIMULATIONS OF SOLUTE TRAPPING AND SOLUTE DRAG
Introduction
Models of Solute Trapping
Solute Drag
MD Simulations
Implications for Dendrite Growth
 
PARTICLE-BASED COMPUTER SIMULATION OF CRYSTAL NUCLEATION AND GROWTH KINETICS IN UNDERCOOLED MELTS
Introduction
Solid - Liquid Interfaces in Nickel
Homogeneous Nucleation in Nickel
Crystal Growth
Conclusions
 
SOLID

Über Autor(innen)

Dieter Herlach is leader of the group "Undercooling of Materials" and Senior Scientist at the Institute of Materials Physics in Space of the
German Aerospace Center (DLR) in Cologne. He is full professor of physics at the Ruhr-University Bochum. Dieter Herlach has authored more than 300 scientific publications in refereed journals and organized sixteen conferences and symposia. He is author and editor of six books and member of the advisory board of Advanced Engineering Materials (Wiley-VCH). He was member of the advisory board of directors of the German Physical Society and deputy chairman of the German Society of Materials Science and Engineering. Two priority programs of the
German Research Foundation (DFG) and several European projects of the European Space Agency and the European Commission were coordinated by him. He was lead scientist for NASA Spacelab missions IML2 and MSL1 and granted as honorary professor of four Chinese Universities and Research Centers.
 
Douglas M. Matson is Vice Chairman and Associate Professor in the Mechanical Engineering Department at Tufts University, Medford MA, USA. He is an internationally recognized expert with over fifty peer reviewed articles in thermal manufacturing, machine design, materials processing, solidification research, and microgravity experimentation. He has organized five symposium, is the former president of the North Alabama Chapter of the American Society for Materials (ASM) and received an Erskine Fellowship at the University of Canterbury, Christchurch, New Zealand. He has served as lead scientist for the MSL-1 Spacelab mission and currently is the NASA facility scientist for the MSL-EML project aboard the International Space Station.