Single Crystal Test Specimens Research Articles

Towards online evaluation of Goss-texture in grain-oriented ferromagnetic sheets

Abstract We propose an experimental method for the identification of the crystal grain orientation in polycrystalline ferromagnetic materials with Goss texture. The grain orientation respect to the lamination plane is evaluated by a suitable contact-less vector measurement of the magnetic field under rotational polarization. First of all, the fundamental in-plane easy axis is detected. After that, the measured data are numerically processed, taking into account a cubic anisotropy grain model, suitably developed, in order to estimate the orientation of the other two crystal axes respect to the lamination plane. The comparison of the obtained results with Electron Back-Scattering Diffractometry (EBSD) measurements confirms the validity of the proposed approach. Multi-grain and single-crystal test specimens are analyzed in order to investigate the possibility to apply this method as on-line detection system.

Stresses in a thin, circular aeolotropic plate subjected to uniform lateral load

Closed form, approximate stress solutions for simply supported cubic and orthotropic plates subjected to a lateral pressure are presented and compared with a series solution. The accuracy of the approximate solutions depends on the degree of anisotropy. For cubic plates exhibiting significant anisotropy, the approximate solution is within ∼10% of the series solution. For a graphite–epoxy composite plate of orthotropic symmetry, the approximate solution is within 10% of the series solution for the maximum stress at the plate centre and within 23% for the minimum stress at the plate centre. Single crystal plates tend to exhibit a large tangential stress where the stiff directions intersect the plate edges, implying that the edges of brittle single crystal test specimens must either be prepared better than those of isotropic specimens or have more of the plate overhanging the support.