Textural evolution of zinc alloys deformed by NECAE method

P. RODRIGUES VERNECK; R.E. BOLMARO

ACTA CRYSTALLOGRAPHICA A

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2011 vol. 67 p. 679 - 679

0108-7673

One of the main methods for increasing mechanical strength is grain refinement. Ultrafine grains can be obtained by means of several methods of Severe Plastic Deformation (SPD) [1], being the most common Accumulative Roll Bonding (ARB), Torsion Straining (TS), Equal-Channel Angular Pressing (ECAP) y Milling Mechanical (MM) [2, 3]. On the current work we study another method of deformation, NECAP [4] (Non Equal-Channel Angular Pressing), by processing sheets of Zn alloys pre-rolled until 0.65 mm thickness and cut into the directions of 0, 45˚ and 90˚ with respect to the original Rolling Direction. Twenty-one plates of 14 mm width and 45 mm length were stacked in the channel matrix, with the plane perpendicular to the transversal direction, and deformed with a load of 5000 kg in a single pass of deformation. The matrix was configured with external and internal angles of Ψ = 81˚ and Φ = 150˚, respectively. We selected four samples for each rolling direction corresponding to different transverse distances of the channel matrix. The samples were characterized by optical microscopy (OM), x-ray diffraction (DRX) and Electron Back Scattering Diffraction (EBSD) analysis. The purpose of the work was to study the deformation texture, microstructural parameters, such as grain size and crystal orientations and local misorientations. The main purpose of the study is a preliminary assessment of shearing deformations that will be applied to another SPD technique: asymmetric rolling of different metals and alloys.