Role of the Mn-Dispersoids and Mg₂Si Particles in the Recrystallization of Automotive 6xxx Alloys

Abstract:

Recrystallization control over the whole process route is strictly needed in order to achieve the required texture and properties. An important factor for this is the different type of particles formed in the material, their size and volume fractions. This study addresses the role of the Mn-bearing dispersoids and the Mg-Si (-Cu) particles, forming during different phases of the sheet processing, thus significantly influencing the recrystallization. It will be shown that, when present, the latter ones are playing an important role in the recrystallization control, not only in promoting the recrystallization by means of Particle Stimulated Nucleation, but also retarding it, if the particle size is sufficiently fine. Moreover, they can completely block the recrystallization, if concurrently precipitating during it. The Mn-dispersoids is comparable in its pinning effect, but takes over only when the Mg & Si atoms are in solid solution. Additionally, an update of the Diagram of Humphreys on the effect of particles on the recrystallization of 6xxx alloys is proposed and discussed.

• Periodical: Materials Science Forum (Volumes 794-796)
• Pages: 1227-1232
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.794-796.1227
• Online since: June 2014
• Authors: Petar Ratchev*, Peter Jessner
• Keywords: Dispersoid, Mg₂Si, Recrystallization

References

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DOI: 10.4028/www.scientific.net/msf.794-796.1227

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