Research into the Flow Stress of Al-Mg-Si Alloy (AD-35) during the Abrupt Change of the Strain Rate at Elevated Temperatures

Abstract:

In industrial practice of rolling and hot forging, i.e. extrusion-type forging, abruptchanges in strain rate during the deformation of the material occur. For accurate numericalsimulation of a forging process, the experimental investigation of the effect of the transient changein strain rate on plastic flow behaviour is necessary. The present paper deals with the investigationof this effect on the flow stress of an AD-35 aluminium alloy during its deformation within thetemperature range of 350-450 °C. During continuous uniaxial compression loading of a cylindricalspecimen, the strain rate was either constant or abruptly increased or decreased from its initial valueat engineering strain of app. 26 %. The following strain-rate histories were applied: 1) constantstrain rate of 0.1, 1.0 and 10 s-1; 2) abrupt strain-rate increasing from 1.0 to 10.0 s-1; 3) abrupt strainratedecreasing from 10.0 to 1.0 s-1. The results of the experimental investigations corresponded tothe transient change in strain rate histories were used to verify the model of softening as well as themodel of hardening of the AD-35 alloy during the abrupt change of the strain rate. It allows todefine these models explicitly.

• Periodical: Key Engineering Materials (Volumes 554-557)
• Pages: 1099-1104
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.554-557.1099
• Online since: June 2013
• Authors: Pavel A. Petrov, Viktor Voronkov, Konstantin Potapenko, Mikhail Petrov, Olga Gamzina
• Keywords: Abrupt Change of Strain Rate, Aluminum Wrought Alloys, QFORM 2D/3D

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