Study of a Topology for Plate Electromagnetic Forming Based on Inner Reverse and Outer Positive Double Coil Loading

Li Qiu,Weikang Ge,Zhang Wang,Wang Bin,Peng Chang,Chang Liu,Ahmed Abu-Siada,Chenglin Wang

doi:10.1109/access.2020.3034097

Abstract

While electromagnetic forming is widely used for aluminum alloy materials, the non-uniformity of plate radial deformation is still a key issue that restricts the wide development of this technology. This article presents a new electromagnetic-forming topology. The proposed topology comprises outer ring double-coil plates along with an inner loop driving coil of a small number of turns whose geometrical parameters are optimized to adjust the induced eddy current of the plate. Numerical simulation results show that the presence of an inner ring driving coil shapes the magnetic field in a manner that the radial electromagnetic force is concentrated close to the edge of the die which affects the center of the plate. With optimum design for the geometrical parameters of the proposed inner ring driving coil, the electromagnetic force distribution can be adjusted over the plate, resulting in an improved plate deformation with an increase in the maximum uniform deformation area from 24mm to 65mm. Results also show that the proposed inner and outer ring double coil loading method possesses superior advantages over the traditional flat spiral coil loading method.

Highlights

With the increased trend of employing lightweight, highstrength and low-density materials in various industrial applications, forming technology has been given much attention [1,2,3]
In order to analyze the axial electromagnetic force acting on the plate and the plate deformation behavior, the parameters of the inner ring driving coil are changed in a wide range as follows:
-The equivalent radius of the inner ring driving coil (Hr), that maintains the cross-sectional area of the inner ring coil constant, is changed from 13.8mm to 37.8mm in steps of 4mm

Summary

INTRODUCTION

With the increased trend of employing lightweight, highstrength and low-density materials in various industrial applications, forming technology has been given much attention [1,2,3]. A new coil system structure is presented in [22], which can generate uniform electromagnetic force on the entire plate and solving the main issue of the traditional sheet electromagnetic forming. This coil structure has been successfully used for processing mobile phone panels. Multiple sets of power supplies to energize multi-sets of driving coils along with a shaft-diameter bidirectional loading plate electromagnetic forming method is presented in [23] This method can improve the performance of plate electromagnetic-forming with a better drawing coefficient (3.25) than that of the traditional drawing process (2.0-2.2). A numerical analysis comparing of the proposed method and the traditional electromagnetic forming is conducted and the plate forming uniformity under the double-coil loading method is discussed

EMF PRINCIPLE AND THE PROPOSED TOPOLOGY

EMF STRUCTURE COUPLING MODEL

SIMULATION RESULTS

Effect of Hi

Effect of Hr

CONCLUSION