Grain Boundary Strain Transfer and Anisotropic Polycrystalline Deformation in Commercial Purity Titanium
The anisotropic nature of polycrystalline deformation in commercially pure titanium has been studied using an array of experimental techniques in compliment with crystal plasticity finite element method (CPFEM) simulations. Analysis has been carried out in the near surface region of a polycrystalline four-point deformation sample .where the global stress state can be approximated as uniaxial tension. Electron backscattered diffraction (EBSD) has been used to map crystal orientations , allowing the active dislocation and twinning systems to be identified based on slip trace analysis of secondary and backscattered electron images. Atomic force microscopy (AFM) measurement of slip step heights allowed quantification of the strain on active deformation systems. Dislocation slip on prism planes was identified as the primary deformation mode,being activated in many soft oriented grains. Nevertheless, significant activation of basal, pyramidal <c+a>, and 10-12 <-1011> extension twins were observed in grains less favorably oriented for prism slip. These observations were compared directly to a columnar 3-D FEM mesh developed to mimic the experimentally characterized microstructure patch. Computational deformation of this patch reproduces many significant characteristics of the experimentally observed deformation behavior,including many aspects of the deformation system activation, crystal rotations, and surface topography development. However,other details of the deformation behavior are not adequately captured, especially the manner in which deformation systems interact with grain boundaries.
Titanium (Ti) deformation anisotropy dislocation twinning strain transfer CPFEM AFM EBSD
Martin A. Crimp Yiyi Yang Leyun Wang Philip Eisenlohr Thomas R. Bieler
Chemical Engineering and Material Science, Michigan State University, East Lansing, MI 48824-1226,US Max-Planck-lnstitut fur Eisenforschung,Max-Planck Straβe 1 ,D-40237Diisseldorf,Germany
国际会议
The 12th World Conference Titanium(第十二届世界钛会 Ti-2011)
北京
英文
1061-1065
2011-06-19（万方平台首次上网日期，不代表论文的发表时间）