The Influence of Low Temperature Clustering on Strengthening Precipitation in Al-Mg-Si Alloys

  • Alex Poznak
  • Paul Sanders

Abstract

Heat-treatable 6000 series aluminum alloys are the most commonly extruded materials in the world. The precipitation process in these alloys is both complex and well characterized. The earliest clustering stage has been shown to have a large effect on subsequent strengthening precipitation, however little is known about the influence of clustering as a function of composition and processing parameters. The current work examines this influence considering the factors of relative and absolute magnesium and silicon content, and the extent of natural aging. Billets were cast and extruded prior to heat-treatment, and the hardening response was evaluated with hardness, conductivity, and transmission electron microscopy (TEM). This work advances the current understanding of Al-Mg-Si precipitation by correlating the kinetics of age hardening to composition and processing, and may lead to further optimization of 6000 series alloy strength and toughness.

Keywords

Aluminum 6000 series natural aging artificial aging clustering precipitation strengthening hardening composition 

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Copyright information

© TMS (The Minerals, Metals & Materials Society) 2016

Authors and Affiliations

  • Alex Poznak
    • 1
  • Paul Sanders
    • 1
  1. 1.Michigan Technological UniversityHoughtonUSA

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