- Previous Article
- Next Article
- Table of Contents
Powder Technology, Vol.219, 1-8, 2012
Consolidation of commercial pure aluminum powder by torsional-equal channel angular pressing (T-ECAP) at room temperature
In the present study, commercial pure aluminum powders were successfully consolidated to nearly full density by a combination of equal channel angular pressing (ECAP) and torsional deformation at room temperature. This new modification of ECAP is named as torsional-equal channel angular pressing (T-ECAP). A mechanism has been suggested to demonstrate the changes in porosities' shape, which leads to the porosities elimination during the T-ECAP process. Metallographic investigations have shown that the shape of the porosities have been changed from an elongated orientation in the ECAP process into near spherical shape in the T-ECAP process. Due to the subsequent torsional strains during the T-ECAP process, pores eliminated more effectively. Density and micro-hardness tests have shown superior values for the samples produced by the T-ECAP process than that of the samples produced using ECAP process, which can be improved by increasing the number of passes. Due to the existence of a variation in porosity from edge to center of the samples produced by both ECAP and T-ECAP processes, a variation in micro hardness in a same trend is also detected. Examination of the mechanical properties of the T-ECAP samples shows some moderate plastic deformation during the compression tests and exhibits high magnitude of ductility with respect to the ECAP samples. (C) 2011 Elsevier B.V. All rights reserved.
Keywords:Severe plastic deformation (SPD);Torsional-equal channel angular pressing (T-ECAP) process;Room temperature consolidation;Compression test;Pore elimination mechanism