Secondary Steelmaking : Principles and Applications

• Synthesizes scientific fundamentals and their practical application.

• Encompasses all aspects of secondary steelmaking - deoxidation, degassing, desulphurization, homogenization, temperature control, and more.

• Offers an integrated analysis and presentation of nitrogen control, inclusions, and clean steel.

• Provides a critical assessment of important thermodynamic data.

The steelmaking industry and its customers have benefited enormously from the many significant technological advances of the last thirty years. As their customers become ever more quality conscious, however, steelmakers must continue their efforts to minimize harmful impurities, minimize as well as modify harmful nonmetallic inclusions and achieve the optimum casting temperature, content of alloying elements, and homogeneity. These improvements can come only through the diverse refinement processes that together comprise "secondary steelmaking."

Secondary Steelmaking: Principles and Applications reviews the scientific fundamentals and explores the various unit processes associated with secondary steelmaking. Synthesizing the science and its technology, the author examines the relevant reactions and phenomena, presents an integrated picture of "clean steel" manufacture, and provides an overview of the mathematical modeling important to process research.

Solved examples, ample references, and summaries of recent technological advances mean that the steelmaking industry finally has a comprehensive reference, in English, for the all-important secondary steelmaking processes. Students and instructors, steelmakers and R & D engineers will welcome the author's readable style, his knowledge, and his expertise, all gleaned from decades of experience in research, academic, and industrial settings.

Preface
About the Author
List of Symbols with Units

Chapter 1 : Introduction
1.1 History of Secondary Steelmaking
1.2 Trends in Steel Quality Demands
1.3 Scientific Fundamentals
1.4 Process Control
References

Chapter 2 : Thermodynamic Fundamentals
2.1 Introduction
2.2 First and Second Laws of Thermodynamics
2.3 Chemical Equilibrium
2.4 G for Oxide Systems
2.5 Activity - Composition Relationships : Concentrated Solutions
2.6 Activity - Composition Relationships : Dilute Solutions
2.7 Chemical Potential and Equilibrium
2.8 Slag Basicity and Capacities
References

Appendix 2.1
Appendix 2.2
Appendix 2.3
Appendix 2.4

Chapter 3 : Flow Fundamentals
3.1 Basics of Fluid Flow
3.2 Fluid Flow in Steel Melts in Gas-Stirred Ladles
References

Appendix 3.1

Chapter 4 : Mixing, Mass Transfer, and Kinetics
4.1 Introduction
4.2 Mixing in Steel Melts in Gas-Stirred Ladles
4.3 Kinetics of Reactions among Phases
4.4 Mass Transfer in a Gas-Stirred Ladle
4.5 Mixing vs. Mass Transfer Control
References

Appendix 4.1

Chapter 5 : Deoxidation of Liquid Steel

5.1 Thermodynamics of Deoxidation of Molten Steel
5.2 Kinetics of the Deoxidation of Molten Steel
5.3 Deoxidation in Industry
References

Appendix 5.1

Chapter 6 : Degassing and Decarburization of Liquid Steel
6.1 Introduction
6.2 Thermodynamics of Reactions in Vacuum Degassing
6.3 Fluid Flow and Mixing in Vacuum Degassing
6.4 Rates of Vacuum Degassing and Decarburization
6.5 Decarburization for Ultra-Low Carbon (ULC) and Stainless Steel
References

Chapter 7 : Desulfurization in Secondary Steelmaking
7.1 Introduction
7.2 Thermodynamic Aspects
7.3 Desulfurization with Only Top Slag
7.4 Injection Metallurgy for Desulfurization
References

Chapter 8 : Miscellaneous Topics
8.1 Introduction
8.2 Gas Absorption during Tapping and Teeming from Surrounding Atmosphere
8.3 Temperature Changes of Molten Steel during Secondary Steelmaking
8.4 Phosphorus Control in Secondary Steelmaking
8.5 Nitrogen Control in Steelmaking
8.6 Application of Magnetohydrodynamics
References

Chapter 9 : Inclusions and Inclusion Modification
9.1 Introduction
9.2 Influence of Inclusions on the Mechanical Properties of Steel
9.3 Inclusion Identification and Cleanliness Assessment
9.4 Origin of Nonmetallic Inclusions
9.5 Formation of Inclusions during Solidification
9.6 Inclusion Modification
References

Chapter 10 : Clean Steel Technology
10.1 Introduction
10.2 Summary of Earlier Chapters
10.3 Refractories for Secondary Steelmaking
10.4 Tundish Metallurgy for Clean Steel
References

Chapter 11 : Modeling of Secondary Steelmaking Processes
Dipak Mazumdar, Ph.D.
11.1 Introduction
11.2 Modeling Techniques
11.3 Modeling Turbulent Fluid Flow Phenomena
11.4 Modeling of Material and Thermal Mixing Phenomena
11.5 Modeling of Heat and Mass Transfer between Solid Additions and Liquid Steel
11.6 Numerical Considerations
11.7 Concluding Remarks
References

Index