Dynamic interactions between precipitation and plastic deformation in aluminium alloys

Dynamic interactions between plastic deformation and precipitation processes in Aluminium alloys can lead to large changes in precipitation kinetics as compared to conventional heat treatments. This can be due to a number of different mechanisms such as changes in vacancy concentrations or movement of structural defects. Understanding the underlying mechanisms requires a quantitative measurement of the precipitate evolution as a function of deformation conditions, temperature and time. The present contribution will review experimental results obtained by Small-Angle X-ray Scattering in three different configurations, all concerning Al-Zn-Mg-Cu alloys: first, dynamic precipitate evolution during plastic deformation at ageing temperature; second, dynamic precipitation during low cycle fatigue at room temperature; and third, precipitation during ageing of a material processed by room temperature high pressure torsion. The experimental evidence will be used to discuss the role of the different mechanisms of interaction with plasticity on the precipitate microstructure evolution.