NEW ANISOTROPIC STRAIN-RATE POTENTIAL FOR HEXAGONAL METALS

Abstract

Theoretical description of plastic anisotropy requires the definition of either stress potentials or plastic strain-rate potentials. In general, strain-rate potentials are more suitable for process design. Existing strain-rate potentials (phenomenological or texture-based) are applicable only to the description of the plastic behavior of materials with cubic crystal structure. Very recently, Cazacu et al. [5] have developed an orthotropic strain-rate potential for hexagonal metals. This strain-rate potential is the exact work-conjugate of the anisotropic stress potential CPB06 of Cazacu et al. [6]. In this paper, a fully implicit time integration algorithm for this potential is developed and applied to the description of the anisotropy and tension-compression asymmetry of high-purity a-titanium. The simulation results confirm the improved capabilities of the model over existing strain-rate potentials and the robustness and accuracy of the integration algorithm.