Experimental Investigation on Formability of AZ31B Magnesium Alloy V-Bending Under Pulse Current

• 来源期刊: 金属学报（英文版）
• 年，卷（期）: 2018,（12）
• 页码范围: 1249-1257
• 页数: 9页
• 语种: 英文

摘要

In this work,the influence of pulse current parameters on springback and bending force of magnesium alloy during electropulse-assisted (EPA) V-bending was investigated.The experimental results showed that pulse current can effectively reduce the springback and the bending force compared to the experiments without current.The frequency has a more significant influence on bending force and springback than electric current density.Electroplastic (EP) effect begins to work when pulse current parameters reach a threshold value.To explore the mechanism of EPA V-bending,the microstructure evolution and fracture surface of the bending specimen were studied.It was found that pulse current can promote the occurrence of dynamic recrystallization (DRX) of magnesium alloy compared to traditional hot forming process.The fracture mode of AZ31B under EPA V-bending evolves from brittle fracture to ductile fracture with increasing pulse current parameters.Based on the discussion of athermal and thermal effects of EP effect,the mechanism of pulse current to promote DRX is studied and athermal effect is proved to exist.