Orientation stability in equal channel angular extrusion. Part II: Hexagonal close-packed materials

✍ Scribed by Saiyi Li

• Publisher: Elsevier Science
• Year: 2008
• Tongue: English
• Weight: 544 KB
• Volume: 56
• Category: Article
• ISSN: 1359-6454
• DOI: 10.1016/j.actamat.2007.11.003

✦ Synopsis

The orientation stability in equal channel angular extrusion (ECAE) of hexagonal close-packed (hcp) crystals using a 90°die is investigated based on the three-dimensional lattice rotation fields from rate-dependent crystal plasticity simulations. The results show that for the major slip and twinning modes considered, the relatively stable orientations in ECAE are distributed along the h1 h to h6 h fibers in the Euler space and feature characteristic alignments of the haior hci-axis with respect to the macroscopic deformation axes. The application of such simulations is demonstrated by comparing the predictions with experimental ECAE textures in high-purity titanium and other hcp polycrystalline materials, including commercial-purity zirconium, beryllium and magnesium alloys. The simulation results for ECAE are also applied to derive the relatively stable orientations in conventional simple shear deformation.