A Numerical Approach to Young's Modulus Evaluation by Conical Indenter with Finite Tip-Radius

유한선단반경을 갖는 원뿔형 압입자에 의한 영률평가 수치접근법

  • 이진행 (서강대학교 대학원 기계공학과) ;
  • 김덕훈 (서강대학교 대학원 기계공학과) ;
  • 이형일 (서강대학교 기계공학과)
  • Published : 2008.01.01


Instrumented sharp indentation test is a well-directed method to measure hardness and elastic modulus. The sharp indenter such as Berkovich and conical indenters have a geometrical self-similarity in theory, but the self-similarity ceases to work in practice due to inevitable indenter tip-blunting. In this study we analyzed the load-depth curves of conical indenter with finite tip-radius via finite element method. Using the numerical regression data obtained from Kick's law, we first confirmed that loading curvature is significantly affected by tip radius as well as material properties. We then established a new method to evaluate Young's modulus, which successfully provides the value of elastic modulus with an average error of less than 2%, regardless of tip-radius and material properties of both indenter and specimen.


Indentation Test;Tip Radius;Young's Modulus;Material Property;FEA


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