Two new types of electrically-assisted forming (EAF) processes of AZ31B magnesium alloy sheets,
i.e., electrically-assisted blanking (EAB) and electrically-assisted sheet upset-extruding (EASUE), are proposed
in this paper. During EAB, pulsed current (PC) decreases blanking load and improves blanked surface quality,
and higher frequency has a more effective improvement; when the frequency reaches 600 Hz, the whole punched
hole fracture is improved to smooth zone. Moreover, EAB does not influence the microstructure and does not
induce obvious annealing, and this process is advantageous to the materials that cannot change microstructure.
During EASUE, PC can reduce extrusion load and enhance extrusion height, and higher frequency also has a
more effective improvement. Both processes indicate that introducing PC can effectively improve the part quality
and have an application prospection.
LIU Kai (刘凯), DONG Xianghuai *(董湘怀), SHI Wen (石文), WANG Xinbao (王新宝), WU Guohong (吴国洪)
. Investigation on Two Electrically-Assisted Forming Processes of AZ31B Magnesium Alloy Sheets[J]. Journal of Shanghai Jiaotong University(Science), 2019
, 24(4)
: 409
-416
.
DOI: 10.1007/s12204-019-2092-4
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