ON THE REVERSIBLE COMPONENT OF PLASTIC FLOW IN TWO-PHASE MATERIALS.

The Bauschinger effect represents a way of estimating the degree of plastic relaxation, and the extent to which back stresses are stored in the material and contribute to the work-hardening. Aluminum-copper aged to give theta prime particles work hardens initially as a plastically inhomogeneous material with a large percentage of the work-hardening due to a back-stress which is stored as rotations in the lattice. These rotations are removed by reverse straining. They are not, however, observed in crystals with a tensile axis very close to left bracket 100 right bracket . As the strain increases, eventually the particles shear.