Pan American Materials Congress: Nanocrystalline and Ultra-fine Grain Materials and Bulk Metallic Glasses: Additional Topics in SPD Processing and Mechanical Properties
Sponsored by: Third Pan American Materials Congress Organizing Committee
Program Organizers: Terence Langdon, University of Southern California; Megumi Kawasaki, Oregon State University; Roberto Figueiredo, Federal University of Minas Gerais; Jose-Maria Cabrera, Universidad Politecnica de Catalunya

Thursday 8:30 AM
March 2, 2017
Room: Marina F
Location: Marriott Marquis Hotel

Session Chair: María Teresa Pérez Prado, IMDEA Materials Institute; Andrea Bachmaier, Erich Schmid Institute of Materials Science

8:30 AM  
Effect of Annealing of ZK60 Magnesium Alloy after Processing by High-pressure Torsion: Seyed Alireza Torbati Sarraf1; Shima Sabbaghianrad1; Terence G. Langdon1; 1University of Southern California
    A ZK60 magnesium alloy with an initial grain size of ~10 μm was processed by high-pressure torsion (HPT) through 5 revolutions under a constant compressive pressure of 2.0 GPa and rotating speed of 1 rpm. An average grain size of ~700 nm was achieved after HPT with a high fraction of high-angle grain boundaries. Tensile experiments at room temperature showed poor ductility. However, combination of reasonable ductility and good strength may be achieved with post-HPT annealing by subjecting samples to high temperature in the range of 473 to 548 K for 10 and 20 min. The grain size and texture changes were also examined by electron back scattered diffraction (EBSD) and results compared to long-term annealing for 2500 min at 450 K. The investigation in this study suggests that a post-HPT annealing for short period of time may be effective in achieving a reasonable combination of strength and ductility.