Einfluss verschiedener Zwischenglühstrategien auf die Biegeeigenschaften von Al-Mg-Si-Fe-Legierungen

Research output: ThesisMaster's Thesis

Abstract

This master's thesis examines the bending properties of Al-Mg-Si-Fe alloys based on the EN AW 6016 alloy system after different annealing strategies. The alloys are synthesized by remelting the Al-Mg-Si alloy 6016 and iron, silicon and manganese were added. An increased content of Fe causes the formation of brittle intermetallic primary phases (AlFeSi-phases), due to its low solubility in the Al lattice, which fragment to individual particles during the rolling process. Besides Fe and Mn, the Si content was intentionally increased to account for its incorporation into the primary phases. Manganese acts as an ¿Fe corrector¿ and has influence on the morphology of Fe-rich primary phases. Additionally, Mn causes the formation of dispersoids during homogenization. Further microstructural components are the soluble phases Mg2Si and Si, which play a major role in the strength of the alloys. The intermediate annealing strategies employed exhibited a pronounced influence on the formation and resulting morphology of Si, which in turn exerted a considerable impact on bendability. The microstructure was analysed using scanning electron microscope and the ImageJ software. Based on the chemical compositions of the alloys thermodynamical calculations were performed using FactSage 8.3. Bending tests revealed varying degrees of influence of the microstructure components on the bendability. In addition, the method of least squares was used to develop formulas for predicting the maximum bending angle based on the phase composition. Moreover, the impact of each individual phase can be derived from the formula parameters. In this regard, it was found that silicon had the most pronounced negative effect on the bendability of the alloys investigated.

Details

Translated title of the contributionInfluence of different intermediate annealing strategies on the bending properties of Al-Mg-Si-Fe-alloys
Original languageGerman
QualificationDipl.-Ing.
Awarding Institution
Supervisors/Advisors
Award date28 Jun 2024
Publication statusPublished - 2024