Stress field induced by intermetallics and grain boundaries: effect on pore nucleation and growth during tensile loading of Al 2050 alloys

It becomes more and more difficult to strictly control the content of iron, which often forms as detrimental intermetallics, during Al production as the demand for recycling Al alloys is increasing. Extensive researches have been performed on the evolution of pores in Al 2050 alloys using in-situ synchrotron micro and nano-tomography, and the resulting analytical models validate pore closure, whilst fail to predict pore growth in tensile mechanical state in the presence of Fe-containing intermetallics. This is mainly due to a lack of good knowledge on the local experimental mechanical state and strain field around pores which is highly influenced by the intermetallics. In this proposal, we will use multi-mode imaging techniques to map the orientations, the stress field (elastic strain) and the global strain field of the matrix grains in 3D, and link such information with the evolution of pores and intermetallic particles during in-situ tensile testing.