ABSTRACT In the aluminum industry, the needs of predictability of the kinetics of precipitation during the artificial aging processes increase as the targeted applications require the maximisation of properties at the lowest costs possible. In this regard, kinetics modelling can be helpful to design the heat treatment processes. Despite using many fitting parameters, available models show a lack of fitting with experimental data, especially for the apparent heat capacity measured at high temperatures by a differential scanning calorimeter (DSC). To address this issue, a mixed-mode model was recently developed for isothermal heat treatment, whereas non-isothermal heat treatment must be considered to compare the calculated results with those measured by isochronal heating in a DSC. In this contribution, the model is extended to non-isothermal heat treatments. To this end, the growth kinetics pathway and sequence of precipitation in a binary Al-Cu alloy have been simulated, optimising the pre-exponential factor and the activation energy of the interfacial mobility of the secondary phases. This calibration of the interfacial mobilities allowed a very good reproduction of the evolution of the apparent heat capacity with temperature. The model and calibrated interfacial mobilities were then used to compute the size evolution of θ′ precipitates in an Al-4 wt%Cu. The isothermal growth rates calculated at 4 temperatures were in good agreement with those measured and reported by independent researchers. The good predictability of the model indicates that the assumptions made were suitable and well funded, especially regarding the growth rates of embryos emerging from the subcritical growth regime. GRAPHICAL ABSTRACT

中文翻译：

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人工时效过程中铝铜合金中析出物生长动力学的多相模拟

摘要在铝工业中，随着目标应用需要以尽可能低的成本实现性能最大化，对人工时效过程中沉淀动力学的可预测性的需求不断增加。在这方面，动力学建模有助于设计热处理工艺。尽管使用了许多拟合参数，但可用模型显示缺乏与实验数据的拟合，特别是对于通过差示扫描量热仪 (DSC) 在高温下测量的表观热容。为了解决这个问题，最近开发了一种用于等温热处理的混合模式模型，而必须考虑非等温热处理，以便将计算结果与 DSC 中等时加热测量的结果进行比较。在这个贡献中，该模型扩展到非等温热处理。为此，模拟了二元 Al-Cu 合金中的生长动力学途径和析出顺序，优化了二次相界面迁移率的指前因子和活化能。界面迁移率的这种校准可以很好地再现表观热容随温度的演变。然后使用模型和校准的界面迁移率来计算 Al-4 wt% Cu 中 θ' 沉淀物的尺寸演变。在 4 个温度下计算的等温增长率与独立研究人员测量和报告的结果非常吻合。该模型良好的可预测性表明所做的假设是合适的且资金充足，特别是关于从亚临界生长机制中出现的胚胎的生长率。图形概要