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Trends in Machine design Original Research

Analysis of Die Corner Gap Formation for Strain Hardening Materials in ECAP Through an Upper Bound Sensitivity Approach: A Comparative Study

  1. Nagendra Singh Department of Mechanical Engineering, Ganeshi Lal Aggarwal University, Mathura
  2. Manoj Kumar Agrawal Department of Mechanical Engineering, Ganeshi Lal Aggarwal University, Mathura
  3. Manish Dixit Department of Mechanical Engineering, Institute of Engineering and Technology, Khandari Campus
  4. Saurabh Pachauri Department of Mechanical Engineering, Institute of Engineering and Technology, Khandari Campus

Abstract

In recent work, using a proposed central composite factorial analysis, the upper-bound theorem's theoretical concept for the equal channel angular pressing process are used. The upper-bound theorem-based theoretical solutions consider Tresca friction conditions and varied fillet radii at the die channel junction. When using AA5083's uniaxial mechanical properties, isotropic nonlinear work hardening is assumed. The ratio of the cumulative effective plastic strain to the time generated by the deformation zones, the effects of strain rate are considered in equal channel angular pressing. In equal channel angular pressing, the load is estimated using an isotropic yield criterion. The billet experiences a simple shear stress state in the equal channel angular pressing process; a noticeable impact of the tooling frictional conditions is evident. Higher values of the ratio between the yield stresses in uniaxial tension or compression and pure shear, or extreme friction conditions, lead to higher levels of equal channel angular pressing load. The suggested composite factorial analysis enables the examination of the primary parameters influencing both the pressure and load in equal channel angular pressing. The outer and inner fillet radii, primarily govern the effective plastic strain. Consistent theoretical predictions indicate that incorporating work-hardening behavior into models, regardless of tribology or tooling arrangements, results in decreased forecasts for pressing force and effective plastic stresses as well as greater die corner angle values. At the deformation zone entrance surface, the immediate workpiece height is related to both the pressing force and the effective plastic strain

Keywords

References (27)

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