Construction of fluidity border taking into account plastic anisotropy

Abstract

Anisotropy due to plastic deformation was studied on tubular steel specimens. This type of anisotropy is found to influence the plastic strain increment vector as the stress point moves over the yield surface associated with a prescribed prestraining. The length of the plastic strain increment vector is found to decrease as the stress point moves from the point associated with the prestraining program. An appropriate measure of this effect is introduced in the form of a modulus of the effective plastic strain increment. Variation of the modulus over the yield surface is compared with the results furnished by the existing flow theories.