Crystal plasticity analysis of texture development in magnesium alloy during extrusion

• Published in: International journal of plasticity 2011-12, Vol.27 (12), p.1916-1935
• Main Authors: Mayama, Tsuyoshi, Noda, Masafumi, Chiba, Ryoichi, Kuroda, Mitsutoshi
• Format: Article
• Language: English
• Subjects: Billets; Compacting; Compressing; Condensed matter: structure, mechanical and thermal properties; Crystal plasticity; Deformation and plasticity (including yield, ductility, and superplasticity); Exact sciences and technology; Extrusion; Finite element analysis; Fundamental areas of phenomenology (including applications); Inelasticity (thermoplasticity, viscoplasticity...); Magnesium; Mechanical and acoustical properties of condensed matter; Mechanical properties of solids; Physics; Plasticity; Slip; Solid mechanics; Structural and continuum mechanics; Surface layer; Texture; Twinning
• ISSN: 0749-6419; 1879-2154
• DOI: 10.1016/j.ijplas.2011.02.007

The texture development mechanism during the extrusion of magnesium alloy is investigated by experimental observation and numerical analysis. First, we perform a finite element analysis of a full extrusion process using a phenomenological constitutive equation, and it is confirmed that the loading condition of the extrusion process near the central axis of the billet is approximated by an equi-biaxial compression mode. Then, the equi-biaxial compression problem is adopted as a simplified boundary value problem to be solved using a crystal plasticity model to clarify the detailed texture development mechanism during the extrusion process. The crystal plasticity analysis of equi-biaxial compression successfully reproduces the texture development from an initial random texture to the final experimentally observed texture. The effects of the deformation modes (i.e. slip and twinning systems) implemented in the calculation and the reference stress ratio of basal to nonbasal slip systems on texture development are studied in detail. Finally, the mechanism of texture development during the extrusion process is discussed in terms of the lattice rotation caused by the activated slip systems.