Development of Hole Expansion Test for Sheet Materials Using Pattern-Recognition Technique

형태 인식 기술을 이용한 판재의 홀 확장성 평가 시스템 개발

  • Jang, Seung Hyun (Dept. of Mechanical Engineering, Kyungpook Nat'l Univ.) ;
  • Kim, Chan Il (Institute of Mechanical Engineering Technology, Kyungpook Nat'l Univ.) ;
  • Yang, Seung Han (Dept. of Mechanical Engineering, Kyungpook Nat'l Univ.) ;
  • Kim, Young Suk (Dept. of Mechanical Engineering, Kyungpook Nat'l Univ.)
  • Received : 2012.05.29
  • Accepted : 2012.10.16
  • Published : 2013.02.04


Nowadays, one of the most interested area of automobile industry is the production of vehicle which has collision safety and ability to produce less amount of $CO_2$. The achievement of such a dual performance is done by choosing the materials like dual phase steel, ferrite bainite steel, etc. These steels have been used in automotive chassis and body parts, and also used to be formed by hole flanging to meet the goal of strength and design requirement. The formability of sheet material was experimented by hole expansion test and the judgement relies on human eye and his experience. This manual judgement involves many errors and large deviation. This paper develops the automatic crack recognition system which finds a crack based on CCD image to complement the problem of the current method depending on human's sense.


Pattern Recognition Technique;Image Processing Technique;Hole Expansion Test;Hole Expansion Ratio(HER)


Supported by : 한국연구재단


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