High entropy alloys (HEAs) represent a class of multicomponent alloys that have garnered significant attention within materials community over the past two decades, largely due to their potential for high-temperature applications. It is essential to comprehend the diffusion behavior within these systems as it forms the foundational basis for designing and developing materials for specific uses, especially in high-temperature applications where the sluggish diffusion effect plays a pivotal role in enhancing material properties. Nevertheless, the existence and extent of the sluggish diffusion effect in these materials have been vigorously debated. Our understanding of this effect in HEAs remains limited, primarily because practical techniques for determining multicomponent diffusion behavior are lacking. This is also the reason that the data on diffusion in quaternary and higher-order systems are scarce in the literature. This review provides an overview of the present state-of-the-art in diffusion studies within the context of HEAs and explores the potential methodologies. Although the existence of sluggish diffusion in HEAs has been a topic of intense debate, there is currently insufficient experimental evidence to support its presence. Consequently, the review explores potential future research directions that aim to fill the gaps in our understanding of this area.

高熵合金 (HEA) 代表一类多组分合金，在过去二十年中引起了材料界的广泛关注，这主要是由于它们在高温应用方面的潜力。了解这些系统内的扩散行为至关重要，因为它构成了设计和开发特定用途材料的基础，特别是在高温应用中，缓慢的扩散效应在增强材料性能方面发挥着关键作用。然而，这些材料中缓慢扩散效应的存在和程度一直受到激烈争论。我们对 HEA 中这种效应的了解仍然有限，主要是因为缺乏确定多组分扩散行为的实用技术。这也是文献中关于四元及高阶系统扩散数据稀缺的原因。这篇综述概述了 HEA 背景下扩散研究的最新进展，并探讨了潜在的方法。尽管 HEA 中是否存在缓慢扩散一直是激烈争论的话题，但目前没有足够的实验证据支持其存在。因此，该综述探讨了未来潜在的研究方向，旨在填补我们对该领域理解的空白。