Twinning-Detwinning Behavior during Cyclic Deformation of Magnesium Alloy

Metals

Soo Yeol Lee²  Huamiao Wang¹  Michael A. Gharghouri³ 

[1] Materials Science and Technology, Los Alamos National Laboratory, Los Alamos, NM 87544, USA; E-Mail:;Department of Materials Science and Engineering, Chungnam National University, Daejeon 305-764, Korea;Canadian Neutron Beam Centre, Canadian Nuclear Laboratories, Chalk River, ON K0J 1J0, Canada; E-Mail:

关键词: magnesium alloy;    deformation;    twinning;    detwinning;    neutron diffraction;   

DOI  :  10.3390/met5020881

来源: mdpi

【 摘 要 】

In situ neutron diffraction has been used to examine the deformation mechanisms of a precipitation-hardened and extruded Mg-8.5wt.%Al alloy subjected to (i) compression followed by reverse tension (texture T1) and (ii) tension followed by reverse compression (texture T2). Two starting textures are used: (1) as-extruded texture, T1, in which the basal pole of most grains is normal to the extrusion axis and a small portion of grains are oriented with the basal pole parallel to the extrusion axis; (2) a reoriented texture, T2, in which the basal pole of most grains is parallel to the extrusion axis. For texture T1, the onset of extension twinning corresponds well with the macroscopic elastic-plastic transition during the initial compression stage. The non-linear macroscopic stress/strain behavior during unloading after compression is more significant than during unloading after tension. For texture T2, little detwinning occurs after the initial tension stage, but almost all of the twinned volumes are detwinned during loading in reverse compression.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.