A Study of Friction in Microfoming Using Ring Compression Tests and Finite Element Analysis

링 압축시험과 유한요소해석을 이용한 미세성형 공정에서의 마찰특성에 관한 연구

  • Kim, Hong-Seok (Dept. of Mechanical Engineering, Seoul Nat'l Univ. of Technology) ;
  • Kim, Geung-Rok (Dept. of Mechanical Engineering, Seoul Nat'l Univ. of Technology)
  • 김홍석 (서울산업대학교 기계공학과) ;
  • 김긍록 (서울산업대학교 기계공학과)
  • Received : 2010.05.10
  • Accepted : 2010.05.20
  • Published : 2010.10.01


Microforming processes have recently attracted considerable attention from industry and academia since they enable the production of microscale parts using various materials at a high production rate, minimize material loss, and provide parts with excellent mechanical properties. However, for successful development and applications of the microforming process it is critical to take the tribological size effect into consideration because previous studies have shown that traditional friction models for macroscale forming generate significantly erroneous results in the case of microforming. In this paper, we performed scaled ring compression experiments to investigate the tribological size effect of aluminum and brass materials in microforming. The sensitivity of the interfacial friction to the deformation characteristics of the ring was quantitatively analyzed by the finite element analysis. In addition, a friction model based on slip line field and upper boundary techniques was used to theoretically explain the friction mechanism in microforming.


Microforming;Size Effect;Ring Compression Test;Finite Element Analysis


Supported by : 한국연구재단


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