Effect of Extremely Low Frequency Pulse Current Treatment on the Mechanical Properties of Al-Zn-Mg-Cu Aluminum Alloy

doi:10.3901/JME.2022.10.068

Abstract

Abstract: Current-assisted plastic forming is a research hotspot in the field of international advanced manufacturing， and it is also an important development direction for precision forming and manufacturing of high-strength lightweight alloys. The effect of extremely low frequency electric pulse on the mechanical properties of 7075-T6 aluminum alloy is studied. The results show that the tensile strength of 7075-T6 aluminum alloy is reduced by electric pulse-assisted stretching， the elongation of the sample after fracture can be increased by 32.3%， and a linear relationship can be established between the current density and duration and the stress drop. The mechanism of the influence of the timing of electrical-mechanical coupling on the plastic properties of aluminum alloys is revealed. When electrical pulses are applied during the elastic deformation stage， high-speed moving electron flow will destroy the bonding force between atoms, leading to the early appearance of crack sources and reducing the plastic properties of aluminum alloys. While applying electrical pulses during the plastic deformation stage， the high-speed moving electron flow will promote the movement of dislocations and improve the plastic performance of aluminum alloy materials. The research results will help promote the wide application of high-strength aluminum alloys in aerospace, ships, high-speed rail, automobiles and other fields.

Key words: electroplasticity, high-strength aluminum alloy, mechanical properties, timing of electro-mechanical coupling

CLC Number:

TG156

SONG Yanli, HAO Chuanchuan, NING Shiru, WU Wenlin, LIU Peng. Effect of Extremely Low Frequency Pulse Current Treatment on the Mechanical Properties of Al-Zn-Mg-Cu Aluminum Alloy[J]. Journal of Mechanical Engineering, 2022, 58(10): 68-77.

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