Early-stage solute clustering and subsequent precipitation hardening phenomena in aluminum and magnesium alloys

可热处理铝合金具有良好的综合性能，是最重要的工程材料之一，被广泛应用。如果适当地利用它们的硬化能力，这些合金可以达到高强度水平。这一潜力对于汽车面板应用非常重要，在汽车面板应用中，合金可以在油漆烘焙过程中硬化。这种工艺使用具有成本效益的加热时间短和温度低的路线，在此期间合金经历纳米级的结构变化。深入了解这些变化以及制造参数对这些变化方向的影响，可以为优化工艺和最大限度地提高成品强度提供必要的工具。近年来，镁合金在设计轻质结构部件和可降解生物材料方面也引起了人们的极大关注。目前生产的一些镁合金是可热处理的，并已显示出硬化能力。然而，对加工对其硬化行为的影响缺乏透彻的了解。

Heat treatable aluminum alloys have been widely used as one of the most important classes of engineering materials due to their combinations of desirable properties. These alloys can achieve high strength levels if their hardening capability is suitably exploited. This potential is of tremendous importance for automotive panel applications where the alloys can be hardened during paint baking processes. Such processes use cost-efficient routes with short heating times and low temperatures, during which the alloys undergo structural changes at nanometer scale. A deep understanding of these changes and the effect of manufacturing parameters in dictating the direction for these changes can provide the necessary tools for optimizing processes and maximizing the strength of the finished products. Recently, magnesium alloys have also attracted significant attention for the design of lightweight structural components, as well as degradable biomaterials. A number of currently-produced Mg alloys are heat treatable and have shown hardening capability. However, a thorough knowledge of the effect of processing on their hardening behaviour is lacking.