  High-entropy alloys (HEAs) are materials that consist of equimolar or
near-equimolar multiple principal components but tend to form single phases,
which is a new research topic in the field of metallurgy, have attracted
extensive attention in the past decade. The HEAs families contain the
face-centered-cubic (fcc), body-centered-cubic (bcc), and
hexagonal-close-packed (hcp)-structured HEAs. On one hand, mechanical
properties, e.g. hardness, strength, ductility, fatigue, and elastic moduli,
are essential for practical applications of HEAs. Scientists have explored in
this direction since the advent of HEAs. On the other hand, the pursuit of high
strength and good plasticity is the critical research issue of materials.
Hence, strengthening of HEAs is a crucial issue. Recently, many articles are
focusing on the strengthening strategies of HEAs[1-14]. In this chapter, we
reviewed the recent work on the room-temperature elastic properties and
mechanical behavior of HEAs, including the mechanisms behind the plastic
deformation of HEAs at both low and high temperatures. Furthermore, the present
work examined the strengthening strategies of HEAs, e.g. strain hardening,
grain-boundary strengthening, solid-solution strengthening, and particle
strengthening. The fatigue, creep, and fracture properties were briefly
introduced. Lastly, the future scientific issues and challenges of HEAs were
discussed.
