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Solidification Analysis for Surface Defect Prediction of Rheology Forming Process Considering Flow Phenomena of Liquid and Solid Region

액상과 고상의 유동현상을 고려한 레오로지 성형공정의 표면결함예측을 위한 응고해석

  • 서판기 (부산대학교 대학원 정밀기계공학과) ;
  • 정영진 (부산대학교 대학원 정밀기계공학과) ;
  • 강충길 (부산대학교 기계공학부)
  • Published : 2002.10.01

Abstract

Two-dimensional solidification analysis during rheology forming process of semi-solid aluminum alloy has been studied. Two-phase flow model to investigate the velocity field and temperature distribution is proposed. The proposed mathematical model is applied to the die shape of the two types. To calculate the velocities and temperature fields during rheology forming process, the each governing equations correspondent to the liquid and solid region are adapted. Therefore, each numerical model considering the solid and liquid coexisting region within the semi-solid material have been developed to predict the defects of rheology forming parts. The Arbitrary Boundary Maker And Cell(ABMAC) method is employed to solve the two-Phase flow model of the Navier-Stokes equation. Theoretical model basis of the two-phase flow model is the mixture rule of solid and liquid phases. This approach is based on using the liquid and solid viscosity. The Liquid viscosity is pure liquid state value, however solid viscosity is considered as a function of the shear rate, solid fraction and power law curves.

Keywords

Semi-Solid Materials;Two-Phase Flow;Liquid Segregation;Semi-Solid Forging

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