Wide Scale Approach in Aluminium Alloys Microstructure Analyses from Component to Atom Scale in Order to Understand Behavior of New Alloys

Abstract

Aluminium alloys are somehow the workhorse among light metals: spreading from castable, work hardenable to age-hardenable alloys, a wide panel of alternatives is available for the users. Nevertheless, continuous improvement of these alloys is ongoing, looking for higher strength, wider service temperature ranges, and suitability for new manufacturing processes.Likewise, a better knowledge of microstructure and ‘finer’ effects have to be encompassed.A proper multiscale approach and competent preparation are advisable for the best interpretation of the performances of new or ‘revised’ alloys.In this work a case study is presented in which multiscale approach has been used in order to explain the behavior of relatively widely used alloys, and also the problems and solution adopted in order to obtain the best results from microstructural analyses.Wrought age hardenable alloys were analyzed to have a better comprehension of ‘high temperature’ evolution of microstructure. The overall appearance of the microstructure was first identified by optical microscopy. Scanning Electron Microscopy (SEM) was involved to analyze grain size, type and size of secondary phases and texture. The results supported modeling studies related to the effect of grain size and texture. Finally, High Resolution Transmission Electron Microscopy (HR-TEM) investigations helped to understand the modification in the decay of mechanical properties upon extended overaging.