Preface

High-entropy alloys (HEAs) or multi-principal element alloys (MPEAs), proposed by Professor Jien-Wei Yeh and Professor Brian Cantor in 2004, have gained extensive attention in the last decade. As a novel alloy, HEAs have superior mechanical properties when compared to traditional alloys, which make them potential candidates for future structural applications.

In this book, mechanical properties of different types of HEAs are briefly introduced and offer an overview of the HEAs in the metal and alloy fields. Focus is on several important characteristics of HEAs, for example, the measurement index of mechanical properties, deformation behaviors, fatigue performances, fabrication processes, and applications. Key issues related to these topics are also discussed. The appendix is an overview of basic questions and answers related to the mechanical properties of HEAs, such as the definition of HEAs, the different families of HEAs, four main strengthening strategies of HEAs, and various processing methods of HEAs.

The authors would like to thank Zayna Connor, Ph.D., and Karen Marken, the senior managing editor at ASM International, for their kind help in publishing this book. Peter K. Liaw very much appreciates the support from (1) the National Science Foundation (DMR-1611180 and 1809640) with program directors, J. Yang, Ph.D., G. Shiflet, Ph.D. and D. Farkas, Ph.D. as well as, (2) the U.S. Army Research Office (W911NF-13–1-0438 and W911NF-19–2-0049) with program managers, M.P. Bakas, Ph.D., S.N. Mathaudhu, Ph.D. and D.M. Stepp, Ph.D.