Microstructure and mechanical properties of 7475 aluminium alloy processed by SPD methods
|Kinga Wawer 1, Malgorzata Lewandowska 1, Arkadiusz K. Wieczorek 2, Michael J. Zehetbauer 2, Krzysztof J. Kurzydlowski 1|
1. Warsaw University of Technology, Faculty of Materials Science and Engineering (InMat), Wołoska 141, Warszawa 02-507, Poland
SPD techniques are capable of achieving ultrafine grain structures being the basis for outstanding mechanical properties. The aim of this work was to compare the efficiency of two different severe plastic deformation (SPD) techniques, i.e. hydrostatic extrusion (HE) and high pressure torsion (HPT), with respect to the microstructure and mechanical properties of 7475 aluminium being processed from two different initial conditions: (i) solution heat treated and (ii) solution heat treated and aged. It was found that SPD processing leads to a significant grain refinement down to nanometer scale. However, the kinetics of microstructure evolution depends on the initial microstructure and processing route. In the case of HE processing the samples deformed immediately after quenching exhibit higher mechanical strength whereas for HPT processing this is true for aged samples. The results are discussed in terms of the influence of both processing parameters and initial microstructure on mechanical properties of SPD processed 7475 aluminium alloy.
Presentation: Poster at E-MRS Fall Meeting 2007, Acta Materialia Gold Medal Workshop, by Kinga Wawer
See On-line Journal of E-MRS Fall Meeting 2007
Submitted: 2007-05-15 16:17 Revised: 2009-06-07 00:44