journal article·2020-11Open access

Fracture Assessment of Notched Severely Plastic Deformed 7075 Al Alloy under Mode I Loading

Y. Alizadeh, H. Salavati, H. Mohammadi

Physical Mesomechanics· Volume 23· Issue 6

Abstract

Equal channel angular extrusion is an extrusion to refine the microstructure of metals and alloys. This paper presents for the first time the experimental results on effects of the equal channel angular pressing (ECAP) on tensile mechanical properties and ductile fracture strength of 7075 Al alloy. The 7075 Al was subjected to equal channel angular pressing after solution treatment, and significant grain refinement and enhancement in tensile strength and hardness are obtained after equal channel angular pressing. Then, the ductile static strength of ECAP 7075 Al alloy weakened by U-notch is investigated under mode I loading. The criterion based on the averaged value of the strain energy density over a control volume at the notch edge in combination with the equivalent material concept is applied to assess the static strength of specimens. A sound agreement between experimental data and the results obtained from strain energy density criterion is found.
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Research context

OpenAlex topics: Microstructure and mechanical properties · Metallurgy and Material Forming · Metal Forming Simulation Techniques

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