The alloy world could be divided into low-entropy (LEAs), medium-entropy (MEAs) and high-entropy alloys (HEAs) based on the configurational entropy at the random solution state. In HEAs, four core effects, i.e. high entropy, sluggish diffusion, severe lattice distortion and cocktail effects, are much more significant than low-entropy alloys in affecting phase transformation, microstructure and properties. In fact, the degree of the influence from these core effects more or less increases with increased mixing entropy. The trend is gradual from low-entropy alloys to high-entropy alloys. In this article, physical metallurgy of HEAs is discussed with the bridge connected to that of conventional alloys. As disordered and ordered solid solutions are the main constituent phases of alloys, the understanding of solid solutions is fundamental for the understanding of alloys. In addition, as dilute solid solutions have been well treated in current physical metallurgy, concentrated solid solutions from low-entropy to high-entropy alloys are focused in this article. Physical properties are especially emphasized besides mechanical properties.

根据随机溶液状态下的结构熵，合金世界可分为低熵（LEAs），中熵（MEAs）和高熵合金（HEAs）。在HEA中，四个核心效应，即高熵，缓慢扩散，严重的晶格畸变和鸡尾酒效应，在影响相变，微观结构和性能方面比低熵合金更为重要。实际上，随着混合熵的增加，这些核心效应的影响程度或多或少地增加。从低熵合金到高熵合金的趋势是逐渐的。在本文中，讨论了HEA的物理冶金学，并将其与常规合金的桥连接。由于无序有序固溶是合金的主要组成相，固溶体的理解是理解合金的基础。此外，由于稀疏固溶体在当前的物理冶金学中得到了很好的处理，因此本文重点讨论了从低熵合金到高熵合金的浓固溶体。除了机械性能外，还特别强调物理性能。