Change in Hardness Statistics during Isothermal Annealing of Cold-Rolled Aluminum

Tsuyoshi Yukimoto; Hiroshi Utsunomiya; Tetsuo Sakai

doi:10.4028/www.scientific.net/MSF.638-642.469

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Precipitation of β' Phase in a Low Cost Beta Titanium Alloy
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Effect of Cr and Zr Dopes on Hydrogen Behaviour in Rapidly Solidified Aluminium Foils
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Change in Hardness Statistics during Isothermal Annealing of Cold-Rolled Aluminum
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Phases and Structure Characteristics of the Near Eutectic Al-Sl-Cu Alloy Using Derivative Thermo Analysis
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Precipitate Behavior and Microstructure Characterization of An Al-Zn-Mg-Cu Alloy Prepared by Spray Forming Process
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Anisotropy of Bending Properties in Industrial Heat-Treatable Extruded Aluminium Alloys
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Mechanical Performance of Newly Developed Titanium and Zirconium System Alloys for Biomedical Applications
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HomeMaterials Science ForumMaterials Science Forum Vols. 638-642Change in Hardness Statistics during Isothermal...

Change in Hardness Statistics during Isothermal Annealing of Cold-Rolled Aluminum

Abstract:

1050 aluminum sheet was cold-rolled by 50% with mineral oil. Hardness was measured on longitudinal section through the thickness of the rolled sheet. The overall hardness statistics of the as-rolled sheet followed the normal (Gaussian) distribution. Though the sheet was rolled under good lubrication, considerable redundant shear deformation was introduced beneath the surfaces by friction. The layers beneath the surfaces showed higher hardness than the center. The hardness subset statistics in one layer in the thickness also followed normal distribution. Isothermal changes in Vickers hardness statistics and in tensile properties during annealing at 548K were investigated. Beneath the surfaces, the recrystallization initiated and completed earlier than the center. The fully recrystallized sheet also shows the normal distribution of hardness, however the standard deviation is much smaller than that before annealing. The layers beneath the surfaces show lower hardness than the center after recrystallization. The partially recrystallized sheet shows bi-modal distribution of hardness. The partially recrysrallized sheet shows slightly better tensile-elongation balance than both the as-rolled sheet and the sheet-fully recrystallized.