Microstructure and Mechanical Properties of Cold-Rolled Mg-6Al-1Zn Alloy Strip Treated by Electropulsing Treatment

Abstract:

The effect of electropulsing treatment (EPT) on the microstructure and mechanical properties of the cold-rolled Mg-6Al-1Zn alloy strip was investigated. It is found that EPT accelerated the recrystallization behaviour of the cold-rolled Mg-6Al-1Zn alloy strip at a relatively low temperature within a short time of 14 seconds. When the temperature of EPT was 423 K, recovery of Mg matrix happened and few β-Mg₁₇Al₁₂ phaseprecipitated in the Mg matrix. With increasing the temperature to 463 K, recrystallization occurred, accompanying dissolution of β-Mg₁₇Al₁₂ phase. When the temperature was increased to 483 K, complete recrystallization took place and obtained fine microstructure of quasi-single-phase recrystallized grains. The elongation to failurewas increased from the 6.3 % of the rolled strip to 23.5 %, while the tensile strength was decreased from 368 MPa to 300 MPa. Further increasing the temperature of EPT, the apparent grain growth occurred and both the tensile strength and elongation to failure reduced. A mechanism for rapid recrystallization process during EPT was discussed.

• Periodical: Materials Science Forum (Volume 789)
• Pages: 328-335
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.789.328
• Online since: April 2014
• Authors: Yan Bin Jiang, Lei Guan, Guo Yi Tang
• Keywords: Electropulsing Treatment, Magnesium Alloy, Mechanical Property, Recrystallization

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