High-entropy alloys (HEAs) are a class of materials composed of multiple elements in nearly equal proportions. This book provides a comprehensive review of the current state of HEA research. It discusses the design principles, microstructure, and properties of HEAs, highlighting their unique characteristics such as high strength, ductility, and thermal stability. The book also covers various synthesis methods, including casting, solidification, and thin film deposition. It explores the effects of processing parameters on the microstructure and properties of HEAs, as well as their potential applications in various fields. The text emphasizes the importance of understanding the fundamental mechanisms governing HEA behavior, including phase formation, atomic mixing, and structural evolution. It also discusses the challenges associated with HEA development, such as the need for precise control over composition and processing. The book provides a systematic approach to HEA design and highlights the potential of HEAs in advanced engineering applications. It also addresses the limitations of current HEA research, such as the difficulty in achieving uniform composition and the need for further investigation into their long-term stability. The book is a valuable resource for researchers and engineers interested in the development and application of HEAs. It offers a detailed overview of the current state of HEA research and provides insights into future directions for this promising field.High-entropy alloys (HEAs) are a class of materials composed of multiple elements in nearly equal proportions. This book provides a comprehensive review of the current state of HEA research. It discusses the design principles, microstructure, and properties of HEAs, highlighting their unique characteristics such as high strength, ductility, and thermal stability. The book also covers various synthesis methods, including casting, solidification, and thin film deposition. It explores the effects of processing parameters on the microstructure and properties of HEAs, as well as their potential applications in various fields. The text emphasizes the importance of understanding the fundamental mechanisms governing HEA behavior, including phase formation, atomic mixing, and structural evolution. It also discusses the challenges associated with HEA development, such as the need for precise control over composition and processing. The book provides a systematic approach to HEA design and highlights the potential of HEAs in advanced engineering applications. It also addresses the limitations of current HEA research, such as the difficulty in achieving uniform composition and the need for further investigation into their long-term stability. The book is a valuable resource for researchers and engineers interested in the development and application of HEAs. It offers a detailed overview of the current state of HEA research and provides insights into future directions for this promising field.