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Effects of Initial Slug Design on the Earring of a Rectangular Battery Case During Impact Extrusion

충격압출 공정에서 초기 슬러그 디자인이 사각 배터리 케이스의 이어링에 미치는 영향 분석

Lim, J. H.;Choi, S.;Chung, W. J.;Shin, J. H.;Lee, J.
임재혁;최석우;정완진;신정학;이종섭

  • Received : 2015.10.06
  • Accepted : 2015.11.19
  • Published : 2015.12.01

Abstract

In the current paper, the effects of initial slug design on the earring of an Al rectangular battery case manufactured by impact extrusion were studied. During impact extrusion, non-uniform metal flow between the long and the short sides of the battery case leads to earring, which is subsequently trimmed. Process parameters such as friction, aspect ratio of the battery case, the die shape and the forming temperature tend to induce earring because they cause greater non-uniform metal flow. Large aspect ratio of the battery case and high friction between slug and die can greatly affect the earring of a rectangular battery case. To make a rectangular battery case without earring, it is necessary to control metal flow uniformly during impact extrusion. One of the ways to reduce the earring is to control the metal flow of slug at the initial upsetting stage. To analyze the effects of the initial slug design on earring, FE analysis was conducted using DEFORM 3D. Two types of initial slug designs were evaluated where volume was removed along either the width or thickness directions. The results show that the initial slug design can be effective in adjusting the uniformity of metal flow.

Keywords

Impact Extrusion process;Initial Slug Design;Metal Flow;Earring

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