Design & Manufacturing

Korean Society of Die & Mold Engineering (한국금형공학회)
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A study of minimizing edge chipping of coverglass using MR Polishing

MR Polishing을 이용한 커버글라스의 굽힘강도 향상에 관한 연구

  • Lee, Jeong-woo (Department of Mechanical Engineering, Inha University) ;
  • Kim, Ji-Hun (Department of Mechanical Engineering, Inha University) ;
  • Lim, Dong-Wook (Department of Mechanical Engineering, Inha University) ;
  • Ha, Seok-Jae (Department of Mechanical & Automotive Engineering, Dong Seoul University)
  • 이정우 (인하대학교 기계공학과) ;
  • 김지훈 (인하대학교 기계공학과) ;
  • 임동욱 (인하대학교 기계공학과) ;
  • 하석재 (동서울대학교 기계자동차공학과)
  • Received : 2022.03.21
  • Accepted : 2022.03.31
  • Published : 2022.03.31
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Abstract

Coverglass of electronic equipments is thinner and slimmer, so the glass must have good bending strength. In these days, the polishing edge of glass is used by solid tool like grinding wheel. But solid tool leave micro crack or edge chipping in edge of glass. MR polishing is an optimal method by polishing edge of glass. MR polishing is used MR fluid that is a liquid tool. MR polishing doesn't leave tool path or residual stress, micro crack and edge chipping unlike grinding wheel polishing. In this paper, the results of grinding and MR polishing were compared and analyzed to improve bending strength by minimizing edge chipping of cover glass. It was derived that the depth and size of cracks have a significant influence on the bending strength of the glass edge. The edges of the glass using MR grinding were analyzed to have a better surface and higher bending strength than the glass using abrasive wheel grinding. It was confirmed that MR polishing had an effect on strength improvement by effectively removing cracks in the specimen.

Keywords

References

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