Constitutive Models for Final Stage Densification of Powder Compacts with Power-Law Creep Deformation

Power-law 크리프 변형을 따르는 분말 성형체의 말기 치밀화 모델

  • 양훈철 (포항공과대학교 대학원 기계공학과) ;
  • 김기태 (포항공과대학교 기계공학과)
  • Published : 2004.07.01


Constitutive models for final stage densification of metal powder compacts with power-law creep deformation were investigated. The constitutive models were implemented into a finite element program (ABAQUS) by using user subroutine CREEP and, from FEM results, useful densification curves were obtained when hydrostatic and uniaxial stress were applied to the powder compacts at various pressures and temperatures. Because the densification behavior varied as the constitutive models, the equivalent stress surface on each constitutive equation was investigated to analyze the difference of densification behavior.


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