The aim of the present study is to determine interrelations of microstructure length-scale, tensile properties and fracture mechanisms of hypoeutectic Zn-Sn alloys. Three compositions were subjected to transient directional solidification: Zn-10, 20 and 40 wt%Sn. Grainy-faceted cleavage has been observed as the predominant mode of fracture, which propagated across the Zn-rich plate cells. A clear influence of the formed microstructure and proportion of eutectic may be noted in the fracture features, with alveolar structures also appearing in fracture surfaces. Growth laws relating the eutectic spacing with the growth rate are proposed, which are able to encompass both steady-state and transient solidification conditions. Hall-Petch type equations are developed relating the yield and ultimate tensile strengths, σ_y and σ_u, respectively, to the cellular spacing, λ, in which smaller λ values resulted in higher σ_y and σ_u.

本研究的目的是确定亚共晶Zn-Sn合金的显微组织长度尺度，拉伸性能和断裂机理之间的相互关系。对三种组合物进行瞬时定向凝固：Zn-10、20和40 wt％Sn。已经观察到粒面切割是断裂的主要方式，其在富锌板细胞中传播。在断裂特征中可以注意到对形成的微结构和共晶比例的明显影响，并且在断裂表面也出现了肺泡结构。提出了将共晶间距与生长速率联系起来的生长定律，该定律能够涵盖稳态和瞬态凝固条件。霍尔佩奇型方程开发了与屈服和极限拉伸强度，σ _ÿ和σ _ü分别到蜂窝间距，λ，其中λ较小值导致更高的σ _ÿ和σ _ü。