Yield surface,Texture, and Deformation mechanisms in AA5754

Experimental and numerical investigations of
yield surface, texture, and deformation mechanisms in AA5754 over low to
high temperatures and strain rates

• Amit Pandey a, b, , ,
• Akhtar S. Khan a,
• Eun-Young Kim c,
• Shi-Hoon Cho ic, ,
• Thomas Gnäupel-Herold d

• a Department of Mechanical Engineering, University of Maryland, Baltimore County, Baltimore, MD 21250, USA
• b Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6069, USA
• c Department
  of Materials Science and Metallurgical Engineering, Sunchon National
  University, Sunchon, Jeonnam 540-742, Republic of Korea
• d NIST Center for Neutron Research, Gaithersburg, MD 20899-8562, USA

Abstract

The
effects of strain rate and temperature on the yield and flow stress of
AA5754 sheets are presented under uniaxial (tension and compression),
dynamic (tension), and simple shear loading conditions. The present
study investigates the anisotropic behavior of AA5754 sheets through
experiments performed in the rolling (RD), 45° to rolling (DD), and
transverse to rolling (TD) directions at room and elevated temperatures.
The experimental results show that the strain rate sensitivity varied
from negative at room temperature to positive at elevated temperatures
(>150 °C), and the anisotropy was inversely proportional to the
strain rate. Texture analysis was conducted on the specimens after
uniaxial tension and simple shear deformation, using the neutron
diffraction and electron back-scattered diffraction (EBSD) techniques.
Rotation rate maps and orientation stability parameters, determined by
the rate-sensitive model, were used to explain the kinematic stability
of the initial texture components in AA5754 sheets during uniaxial
tension and simple shear deformation. A visco-plastic self-consistent
(VPSC) polycrystal model was used to simulate the evolution of the
initial texture components in AA5754 sheets during uniaxial tension and
simple shear deformation.