Abstract The 3D problem of spreading and solidification of a molten solder droplet (with a melting temperature of Tm and a radius of Rd) on a circular pillar (with a radius Rpillar and a height Hpillar, having a contact angle θpillar at wall temperature Tpillar) above a substrate has important applications in electronic packaging. In this paper, effects of pillar's contact angle and wall temperature on droplet dynamics and solidification of the solder droplet are studied numerically based on a newly developed 3D multi-component, triple- phase-change LB model. For pillar's wall temperature equal to the melting temperature of the molten droplet (Tpillar = Tm), no solidification takes place in the droplet after its contact with the pillar, and droplet's spreading characteristics depend on the pillar's contact angle. If pillar's contact angle (θpillar) is smaller than a critical contact angle (θpillar)cr, i.e., θpillar

中文翻译：

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用于电子封装的熔融焊料滴在支柱上润湿和固化的 3D 数值研究

摘要 熔融焊料滴（熔化温度为 Tm，半径为 Rd）在圆柱（半径为 Rpillar，高度为 Hpillar，壁温为 Tpillar，接触角为 θpillar）上扩散和凝固的 3D 问题上面的基板在电子封装中具有重要的应用。在本文中，基于新开发的 3D 多组分三相变 LB 模型，数值研究了支柱接触角和壁温对焊滴动力学和焊滴凝固的影响。当柱壁温度等于熔滴的熔化温度（Tpillar = Tm）时，液滴与柱接触后不会发生凝固，液滴的扩散特性取决于柱的接触角。如果支柱'