Effect of ECAP on the Dimensional and Morphological Characteristics of High Performance Aluminium PM Alloy
The main aim of this paper is to show how ECAP influences the porosity distribution of PM aluminium alloys. The dimensional and morphological characteristics of investigated materials were measured individually for each pore. A commercial ready-to-press aluminium based powder (ECKA Alumix) was used as material to be investigated. After applying different compacting pressures (400 - 700 MPa), specimens were debinded in a ventilated furnace (Nabertherm) at 400 °C for 60 min. Sintering was carried out in a vacuum furnace at 610 °C for 30 min. The specimens were ECAPed for 1 pass. When severe plastic deformation is applied, the stress distribution in deformed specimens causes the powder particles to squeeze together to such an extent that the initially interconnected pores transform to small isolated pores, determining a given value of the dimensional characteristics. Consequently, ECAP influences the porosity distribution in terms of the involved severe shear deformation and therefore influences the pore morphology.
Jing Tao Wang, Roberto B. Figueiredo and Terence G. Langdon
J. Bidulská et al., "Effect of ECAP on the Dimensional and Morphological Characteristics of High Performance Aluminium PM Alloy", Materials Science Forum, Vols. 667-669, pp. 535-540, 2011