The primary spacing is intrinsically linked with the mechanical behavior of directionally solidified materials. Because of this relationship, a significant amount of solidification work is reported in the literature, which relates the primary spacing to the process variables. This review provides a comprehensive chronological narrative on the development of the directional dendritic growth problem over the past 85 years. A key focus within this review is detailing the relationship between key solidification parameters, the operating point of the dendrite tip, and the primary spacing. This review critiques the current state of directional dendritic growth and primary spacing modelling, briefly discusses dendritic growth computational and experimental research, and suggests areas for future investigation.

中文翻译：

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定向树突生长和初级间距的研究进展

主要间距与定向凝固材料的机械性能本质上相关。由于这种关系，文献中报道了大量的固化工作，这将主要间距与工艺变量相关联。这篇综述提供了关于过去85年中定向树突生长问题发展的综合时间顺序叙述。本次审查的重点是详细说明关键凝固参数，枝晶尖端的工作点和一次间距之间的关系。这篇评论批评了定向树突生长和初级间距建模的当前状态，简要讨论了树突生长的计算和实验研究，并提出了需要进一步研究的领域。