Investigation of the Effect of Homogenization Practice of 6063 Alloy Billets on Beta to Alpha Transformation and of the Effect of Cooling Rate on Precipitation Kinetics

Abstract:

A joint research project was accomplished with the aim to determine the effect of homogenization conditions (temperature, time, cooling rate) on the microstructure and hardness of 6063 alloy billets. Homogenization is crucial for the ability to extrude the piece in low cost, but mainly without defects. Thus, it is of importance to determine the most suitable homogenization conditions (temperature, time, cooling rate) and its effect on both microstructure and hardness of 6063 alloy billets. Furthermore, the size and morphology of the AlFeMnSi intermetallic particles (mean diameter, aspect ratio) and the precipitation behavior of Mg₂Si constituents are examined in detail via optical (OM) and scanning electron microscopy (SEM). The resulting mean diameter and aspect ratio data generated by such measurements using OM and image analysis of the intermetallics, that are relevant to the extent of beta-to-alpha transformation, are statistically processed with “ANOVA”. Differential Scanning Calorimetry (DSC) tests are used to determine the coherency level of the particles that were precipitated during the different cooling rates and to reveal the potential for resolutioning the precipitates during billet preheating. Samples received from the plant are compared to laboratory samples in order to facilitate the process of optimization the thermal treatment and improve extrudability.

• Periodical: Materials Science Forum (Volume 941)
• Pages: 884-889
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.941.884
• Online since: December 2018
• Authors: Marianna Katsivarda, Athanasios Vazdirvanidis*, George Pantazopoulos, Nikos Kolioubas, Sofia Papadopoulou, Andreas Rikos, Eugenia Spiropoulou, Spyros Papaefthymiou
• Keywords: 6063, ANOVA, Cooling Rate, Homogenization, Transformation

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