Abstract We examine the apparent size of the core and shell as a function of cooling rate in core–shell particles of the metastable monotectic alloy Co-50 at% Cu, finding that the volume fraction of the core systematically increases with cooling rate and hence undercooling. A model for this variation is proposed. A Monte-Carlo simulation is used to correct for sectioning effects allowing the true core:shell volume ratio to be estimated. From this, and the observation of a second, spinodal, episode of liquid phase separation we are able to estimate the undercooling at solidification. This permits a calculation of the time available following liquid phase separation for the migration giving rise to the observed core–shell structure to occur and hence the required Marangoni velocity required to such migration.

中文翻译：

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滴管加工亚稳态单晶合金中核壳颗粒形成的动力学

摘要 我们检查了作为亚稳态偏晶合金 Co-50 at% Cu 的核壳颗粒中冷却速率的函数的核和壳的表观尺寸，发现核的体积分数随着冷却速率系统地增加，因此过冷. 提出了这种变化的模型。Monte-Carlo 模拟用于校正切片效应，从而可以估计真实的核壳体积比。据此，以及对第二次、旋节线、液相分离事件的观察，我们能够估计凝固时的过冷。这允许计算液相分离后用于迁移的可用时间，导致观察到的核壳结构发生，因此需要这种迁移所需的 Marangoni 速度。