|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Strip Casting of Light Metals
||Microstructure Investigations of Inverse Segregations in Twin-roll Cast AZ31 Strips
||Christina Krbetschek, Franz Berge, Matthias Oswald, Madlen Ullmann, Rudolf Kawalla
|On-Site Speaker (Planned)
During twin roll casting remaining melt, enriched with alloying elements, is pressed into small cavities of rapid solidified material at the chill surface. This phenomenon is called inverse segregation and can be formed during the twin-roll casting of AZ31. Under mechanical load, inverse precipitations in AZ31 strips in annealed conditions act as crack initiator and lead to material failure below the maximum deformation limits. For determining the qualitative chemical composition of the inverse segregations, SEM investigations using the EDX analysis were carried out. In order to specify the individual phases of the precipitations, the qualitative X-ray phase analysis was applied. Potential generation mechanisms of inverse segregations during TRC, based on the present results, were discussed. Via tensile tests at room temperature, the influence of the inverse segregations on the elongation to failure A80 in heat treated AZ31 TRC sheets was proved. Magnesium sheets with and without inverse segregations were compared.
||Planned: A combination print-CD volume