High‐entropy alloys (HEAs) composed of multiprincipal elements with near‐equiatomic ratio have gained numerous attention in recent years. The design concept and unique microstructure make them exhibit a wide range of attractive properties, promoting them suitable for most structural and functional applications. HEAs have four core effects: severe lattice distortion, high entropy, sluggish diffusion, and cocktail effects, which are all interconnected. Among these core effects, severe lattice distortion is seen as the most key factor in determining the properties of HEAs. Recent findings prove that phase selection in HEAs cannot be described by the maximized entropy theory alone. As such, the phase formation principles in terms of single‐phase and multiphase formation criteria are summarized. Severe lattice distortion affecting the mechanical properties and polymorphism of HEAs is reviewed. Several strategies, which have recently been successfully applied in overcoming the “strength–ductility trade‐off” in HEAs, are discussed. Some key unsolved questions concerning the lattice distortion in HEAs which could be interesting research topics in the future are suggested.

中文翻译：

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高熵合金的相选择，晶格畸变和力学性能

近年来，由近等原子比的多主要元素组成的高熵合金（HEA）引起了广泛关注。设计理念和独特的微观结构使其具有广泛的吸引力，从而使其适合大多数结构和功能应用。HEA具有四个核心影响：严重的晶格畸变，高熵，缓慢的扩散和鸡尾酒效应，它们都是相互关联的。在这些核心效应中，严重的晶格畸变被视为决定HEA特性的最关键因素。最近的发现证明，仅用最大熵理论不能描述HEA中的相选择。因此，总结了根据单相和多相形成标准的相形成原理。综述了影响HEA力学性能和多态性的严重晶格畸变。讨论了最近成功用于克服HEA中的“强度-延性权衡”的几种策略。提出了一些有关HEA中晶格畸变的未解决关键问题，这些问题将来可能成为有趣的研究课题。