Additive Manufacturing: Understanding the Effects of Thermal Processing on Designer Aluminum Alloys for Additive Manufacturing

Metal powder-based additive manufacturing (AM) processes often utilize feedstock materials with properties not optimized for the associated processing conditions. Thus, it is necessary to design powders specifically for AM applications, including both traditional and solid-state processes, to allow for desired processing and performance. In this study, an aluminum alloy designed for traditional AM was analyzed for use in solid-state additive processes. The powder's microstructure directly affects its properties and can be finely controlled with thermal treatments. Therefore, several heat treatments were explored to manipulate the powder's microstructure for optimal performance in the final processed part. Analysis of the powder and the AM-processed part was completed using scanning electron microscopy, transmission electron microscopy, energy dispersive x-ray spectroscopy, x-ray diffraction and nanoindentation, guided by computational thermodynamic and kinetic modeling.