The research development of channel segregation (freckle) during solidification in multi-component systems is discussed, including the freckle characteristic, influencing factor and physical feature.

• 摘要对多组元复杂体系（尤其是高温合金体系）在凝固过程中形成的通道偏析即黑斑的研究现状进行了评述，包括黑斑的存在方式、影响因素和物理特征等。