The Domain of Portevin-Le Chatelier Effect in Al-3Mg Alloy

Abstract:

An Al-3Mg (wt. %) alloy was studied after equal channel angular pressing and subsequent cold rolling. The mechanical behavior of the alloy in the temperature range from 223 K to 373 K (from –50°C to 125°C) at strain rates 2.1×10^–1 – 5.2×10^–5 s^–1 was investigated. The analysis of stress-strain curves was performed to determine the conditions of manifestation of the Portevin – Le Chatelier (PLC) effect in investigated alloy. The deformation curve at a temperature of 298 K (25°C) and a strain rate of 1×10^–3 s^–1 is characterized by instability of plastic flow in contrast to the deformation curves obtained under other studied strain rate/temperature conditions. Stress oscillations at the necking stage were observed at high temperatures (>323 K (50°C)) and lower strain rates (1×10^–4 s^–1 and 5.2×10^–5 s^–1) forming the left border of the PLC effect domain. In general, deformation curves are characterized by the absence of stress serrations during the uniform elongation.

• Periodical: Materials Science Forum (Volume 1016)
• Pages: 928-933
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.1016.928
• Online since: January 2021
• Authors: Anna Mogucheva*, Diana Yuzbekova, Yuliya Igorevna Borisova
• Keywords: Aluminum Alloy, Mechanical Testing, Portevin-Le Chatelier Effect, Severe Plastic Deformation

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