Chapter 1  General Introduction
  1.1  Techniques for Removal of Nonmetallic Inclusions from Steel
    1.1.1  Overview of Nonmetallic Inclusions in Steel
    1.1.2  The Development Status of Non-Bubble Inclusion Removal Technology
    1.1.3  Development of Inclusions Removal Technology by Bubbles
  1.2  Mechanism of Bubble Removal of Inclusions
    1.2.1  The Mechanism of Inclusion Removal by Bubble Adhesion
    1.2.2  The Mechanism of Inclusion Removal by Large Bubble Wake
  1.3  Study of Bubble Nucleation
    1.3.1  Homogeneous Bubble Nucleation
    1.3.2  Bubble Heterogeneous Nucleation
  1.4  Study of Bubble Growth
    1.4.1  The Growth of a Stationary Bubble
    1.4.2  The Growth of Bubble During in the Process of Rising
  1.5  The Influence of Different Factors on the Removal of Inclusions by Bubbles
    1.5.1  The Effect of Bubble Size and Dispersion Degree on Inclusion Removal
    1.5.2  Effect of Inclusion Size on Inclusion Removal
    1.5.3  Effect of Contact Angle on Inclusion Removal
  1.6  The Research Significance and Content of this Book
  References
Chapter 2  Theoretical Analysis of Bubbles Nucleating on Surfaces of Convex Spherical Inclusions in Molten Steel During Vacuum Treatment
  2.1  Introduction
  2.2  Experimental
  2.3  Modeling on Thermodynamics of Bubbles Nucleating on Convex Spherical Inclusions
    2.3.1  Interfaeial Contact Angle ＞90°
    2.3.2  Interracial Contact Angle ≤90°
  2.4  Results and Discussion
    2.4.1  The Difference between Convex Spherical Surface Nucleation and Flat Substrate Nucleation
    2.4.2  Intluenee of Inclusion Radius on Bubble Nucleation
    2.4.3  Influence of Melt Depth on Bubble Nucleation
    2.4.4  Intluenee of Contact Angle on Bubble Nucleation
    2.4.5  Influence of Pretreatment Pressure on Bubble Nucleation
    2.4.6  Influence of Vacuum Treatment Pressure on Bubble Nucleation
    2.4.7  Experimental Results
  2.5  Conclusions
  References
Chapter 3  Bubble Growth and Floating Behavior during Degassing Process of Molten Steel/( N2, H2 ) System
  3.1  Introduction
  3.2  Modeling on Kinetics of Bubble Growth and Floating Behavior in Steel/( N2, H2 ) System
    3.2.1  Assumptions
    3.2.2  The Differential Equation for Floating Velocity of Bubbles
    3.2.3  The Differential Equation for Growth Rate of Bubbles
    3.2.4  The Differential Equation for Floating Distance of Bubbles
  3.3  Water Model Experiment
    3.3.1  Experimental
    3.3.2  Modeling on Kinetics of Bubble Growth and Floating Behavior in Water/CO2 System
    3.3.3  Results and Analysis
  3.4  Discussion
    3.4.1  Influence of Pretreatment Pressure on Bubble Growth and Floating Behavior
    3.4.2  Influence of Gas Type on Bubble Growth and Floating Behavior
    3.4.3  Influence of Nucleation Depth on Bubble Growth and Floating Behavior
    3.4.4  Influence of Inclusion Size on Bubble Growth and Floating Behavior
    3.4.5  Influence of Vacuum Treatment Pressure on Bubble Growth and Floating Behavior
    3.4.6  Analysis of Inclusion Removal Mechanism
  3.5  Conclusions
  References
Chapter 4  Study on Removal of Inclusions from Silicon Manganese Deoxidized Steel by Nitrogen Addition and Nitrogen Evolution
  4.1  Introduction
  4.2  Experiment
    4.2.1  Experimental Equipment and Materials
    4.2.2  Experimental Methods
  4.3  Experimental Results
    4.3.1  Changes of TIN] andT[O] in Steel
    4.3.2  Characteristics and Removal Effect of Inclusions in Steel
  4.4  Discussion
    4.4.1  Influence of Nitrogen Increasing Pressure on Bubble Nucleation in Steel
    4.4.2  Influence of Nitrogen Increasing Pressure on Bubble Density
  4.5  Conclusions
  References
Chapter 5  The Mechanism of Inclusion Removal from Molten Steel by Dissolved Gas Flotation
  5.1  Introduction
  5.2  Experimental
    5.2.1  Dissolved Nitrogen Gas Flotation Experiment in Vacuum Inductive Furnace
    5.2.2  Water Model Experiment
  5.3  Results and Discussion
    5.3.1  Solubility of Nitrogen in Liquid Steel
    5.3.2  Residual Gas and Inclusion after DGF Refining
    5.3.3  Manners of Inclusion Removal by DGF
    5.3.4  Mathematical Calculation for Bubbles Flotation in Liquid Steel
  5.4  Conclusions
  References
Chapter 6  Production of Clean Steel Using the Soluble Gas Flotation Method
  6.1  Introduction
  6.2  Industrial Experiments
  6.3  Results
    6.3.1  Changes of Nitrogen/Oxygen Content in Steel
    6.3.2  The Type and Morphology of Inclusions in Billets
    6.3.3  Effect of Inclusion Removal
  6.4  Discussion
    6.4.1  The Effect of Nitrogen Content on Depth Range of Bubble Nucleation
    6.4.2  Effect of Nitrogen Content on Bubble Nucleation Rate
    6.4.3  The Mechanism of PERM and SGFT
  6.5  Conclusions
   References
Chapter 7  The Effects of Soluble Gas Flotation Technology on the Flow Field of Ladle and Inclusion Removal in RH Refine Process
  7.1  Introduction
  7.2  Experimental
    7.2.1  RH Water Model
    7.2.2  Experimental Program
  7.3  Results and Discussion
    7.3.1  Behavior of Bubbles in the Ladle of RH Water Model
    7.3.2  Analysis of Nucleation Mechanism of Bubbles in RH Water Model and Prototype
    7.3.3  Effects of SGFT on Flow Field in RH Ladle
    7.3.4  Effects of SGFT on Flow Pattern and Mixing Time of RH Ladle
    7.3.5  Analysis of the Trajectory and Inclusion Removal Mechanism of Bubbles in RH Degasser
    7.3.6  Effect of SGFT on Particle Removal in RH Water Model
  7.4  Conclusions
  References
Chapter 8  Water Model Study of the Removal Effect of Soluble Gas Flotation Technology on Inclusions with Different Characteristics
  8.1  Introduction
  8.2  Experimental
    8.2.1  Raw materials and Experimental Apparatus
    8.2.2  Experimental Procedure
  8.3  Results and Discussion
    8.3.1  Behavior of Bubbles in the Water Model
    8.3.2  The Effects of the Particle Number on the Removal Rate
    8.3.3  The Effects of the Particle Size on the Removal Rate
    8.3.4  The Effects of the Particle Type on the Removal Rate
  8.4  Conclusions
  References
List of Symbols
List of Figures
List of Tables
Acknowledgements