Stereologische Analyse der mikrostrukturellen Inhomogenitäten in durch Kokillenguss mit Direktkühlung und durch konventionellen Strangguss verarbeiteten Aluminium-Magnesium-Legierung (AA5754)

In this study, quantitative microstructural investigations were performed to understand the influence of the processing route on the grain and particle structures in an Al-Mg alloy (AA5754) The microstructures of two different batches of 5754-O sheets of the same composition (one produced by direct-chill casting (DC) and the other by continuous casting (CC)) were investigated using optical, scanning and transmission electron microscopy. Several characteristic microstructural features were linked to the processing route, especially the banding of the Fe-rich constituent particles along the rolling direction (RD) combined with a through-thickness variation in grain size alloys produced by CC, compared to a random particle distribution of relatively coarser sizes and a roughly uniform through-thickness grain size distribution in the alloys produced by DC The study also assessed the significanoe of the characteristic microstructural features associated with DC and CC (e.g. particle size banding and grain size variation) on the identification the processing route, highlighting the features that represent inconclusive evidence for a certain route.