This book provides a detailed overview of high entropy materials and alloys, discussing their structure, the processing of bulk and nanostructured alloys as well as their mechanical and functional properties and applications. It covers the exponential growth in research which has occurred over the last decade, discussing novel processing techniques, estimation of mechanical, functional and physical properties, and utility of these novel materials for various applications. Given the expanding scope of HEAs in ceramics, polymers, thin films and coating, this book will be of interest to material scientists and engineers alike.
Author(s): Krishanu Biswas, Nilesh Prakash Gurao, Tanmoy Maiti, Rajiv S. Mishra
Series: Materials Horizons: From Nature to Nanomaterials
Publisher: Springer
Year: 2022
Language: English
Pages: 475
City: Singapore
Foreword
Preface
Acknowledgments
Contents
About the Authors
1 High Entropy Materials (HEMs): An Overview
1.1 Alloys Why So Important for Civilization
1.2 Advent of HEMs: Why Multicomponent Equiatomic Alloys Were Not Extensively Investigated Earlier?
1.3 Research on HEMs—How It Started?
1.3.1 Research Done by Pioneers
1.3.2 J.-W. Yeh
1.3.3 S. Rangananthan
1.3.4 Jon-Paul Maria and Jian Luo
1.4 High Entropy Materials—Basic Concepts
1.5 Entropy versus Enthalpy
1.6 HEM Family
1.7 HEMs and Beyond
1.8 Properties
1.9 The Scope of the Book
References
2 High Entropy Materials: Basic Concepts
2.1 Introduction
2.2 Emergence of Four Core Effects—Framing the Basic Concepts
2.2.1 The High Entropy Effect
2.2.2 The Lattice Distortion Effect
2.2.3 The Sluggish Diffusion Effect
2.2.4 The “Cocktail” Effect
2.3 High Entropy Alloys and Ceramics: Definition and Classification
2.3.1 Constituent Element-Based Classification
2.3.2 Traditional Crystal Structure-Based Classification
2.3.3 Microstructure-Based Classification
2.3.4 Density-Based Classification
2.3.5 Deformation Mechanism-Based Classification
2.4 Composition Notation
References
3 Phase and Microstructural Selection in High Entropy Materials
3.1 Introduction
3.2 Alloy Design Strategies
3.2.1 Predicting Solid Solubility from Hume-Rothery Rules
3.2.2 Parametric Approach
3.2.3 CALPHAD Approach
3.2.4 Ab Initio Approach
3.2.5 Pettifor Map Approach to Predict the Formation of HEMs
3.3 Phase Selection Approach to Find Single Phase Versus Multiphase HEMs
3.4 Design Strategies for High Entropy Ceramics (HECs)
3.5 Microstructure of HEMs
3.6 Design Strategies for High Entropy Metallic Glasses
3.6.1 Trial and Error Method
3.6.2 Nearly-Free-Electron Method
3.6.3 Valence Electron Concentration Method
3.6.4 Discrete Variational Method
3.6.5 Machine Learning Methods
References
4 Diffusion in High Entropy Materials
4.1 Introduction
4.2 Diffusion in Alloys
4.3 Diffusion in Multicomponent Systems
4.4 Measured Diffusivities in High Entropy Alloys—Validity of the Core Concept of Sluggish Diffusion
4.5 Implications for Diffusion-Controlled Processes
4.5.1 Creep and Superplasticity
4.5.2 Diffusional Solid State Phase Transformation in HEAs—Phase Separation and Precipitation
4.5.3 Grain Growth in HEAs
References
5 Application of Artificial Intelligence in the Design of HEMs
5.1 Introduction
5.2 ICME
5.2.1 CALPHAD
5.2.2 Ab Initio
5.2.3 DFT/MD Simulation
5.2.4 MC Simulation
5.2.5 Phase-Field Simulations
5.2.6 Machine Learning Approaches
5.3 Future Outlook and Summary
References
6 Synthesis and Processing of Bulk High Entropy Materials
6.1 Introduction
6.2 Processing of HEAs
6.2.1 Melting and Casting Route
6.2.2 Powder Metallurgical Processing Route
6.3 HEA-Based Composites
6.4 High Entropy Ceramics: Oxides, Carbides, and Borides
6.5 Combinatorial Materials Synthesis
6.6 Additive Manufacturing
6.7 Summary
References
7 Synthesis and Processing of HEA Coating and Thin Films
7.1 Introduction
7.2 HEA Coatings: Challenges
7.2.1 Mechanical Alloying
7.2.2 Spray Technique
7.2.3 Laser Cladding
7.3 HEA Thin Films: Preparation and Challenges
7.3.1 Sputtering Technique
7.3.2 Ion Beam Sputter Deposition (IBSD)
References
8 Structural Properties
8.1 Introduction
8.2 Hot and Cold Working of HEAs
8.2.1 Hot Working of HEAs
8.2.2 Cold Working of HEAs
8.2.3 Severe Plastic Deformation
8.3 Mechanical Properties of HEAs
8.3.1 Elastic Properties
8.3.2 Quasistatic Tensile Behavior
8.3.3 Transient Plastic Deformation
8.3.4 Dynamic Tensile Behavior
8.3.5 Fracture Toughness
8.3.6 Strength Ductility Paradox
8.3.7 Hardness and Wear Resistance
8.3.8 Fatigue
8.3.9 Creep and Superplasticity
8.4 Corrosion and Oxidation
8.5 Summary
References
9 Functional Applications of High Entropy Alloys
9.1 Introduction
9.2 Magnetism
9.3 Electronics
9.4 Thermoelectrics
9.5 Hydrogen Storage
9.6 Catalytic Application
9.7 Sensor Application
References
10 Summary and Future Direction
10.1 Introduction
10.2 Goals of Property Improvement
10.3 Advanced Applications Requiring HEMs
10.4 Technology Development
10.5 Patents on HEMs
10.6 Future Direction
References
Appendix A
Appendix B
List of Patents
Appendix C
References
