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Strength Estimation of Die Cast Beams Considering Equivalent Porous Defects

다이캐스팅 보의 등가 기공결함을 고려한 강도평가

  • 박문식 (한남대학교 기계공학과)
  • Received : 2016.02.15
  • Accepted : 2016.12.28
  • Published : 2017.05.01

Abstract

As a shop practice, a strength estimation method for die cast parts is suggested, in which various defects such as pores can be allowed. The equivalent porosity is evaluated by combining the stiffness data from a simple elastic test at the part level during the shop practice and the theoretical stiffness data, which are defect free. A porosity equation is derived from Eshelby's inclusion theory. Then, using the Mori-Tanaka method, the porosity value is used to draw a stress-strain curve for the porous material. In this paper, the Hollomon equation is used to capture the strain hardening effect. This stress-strain curve can be used to estimate the strength of a die cast part with porous defects. An elastoplastic theoretical solution is derived for the three-point bending of a die cast beam by using the plastic hinge method as a reference solution for a part with porous defects.

Keywords

Die Casting;Porosity;Mori-Tanaka Method;Plastic Hinge;Three Point Bent Beam;Finite Element Method

Acknowledgement

Supported by : 한남대학교

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