The Bauschinger Effect of Aluminum Single Crystals Tested under Plane-Strain Compression

Abstract

A plane-strain compression test was made to investigate the Bauschinger effect in aluminum single crystals which deform by multiple slip. First, the testing method, especially as to the clearance and the lubrication between crystal and die, was discussed in comparison with torsion test. The Bauschinger curves of crystals with various non-symmetrical orientations were represented by the shear stress and the shear strain determined from the forward and the reverse compression data using the analysis of Taylor-Bishop-Hill. Here, in the reverse compression the free plane of crystal in the forward compression was compressed without changing the restricted plane. The analysis did not always produce satisfactory results in the permanent softening. This is due to the lattice rotation during deformation. Nevertheless, the average curve of single crystals was found to be in good agreement with the Bauschinger curve of polycrystal. Furthermore, the dislocation structure was examined by transmission electron microscopy and also an examination of slip system derived from the analysis was tried.