Thematic Unit of Excellence on Computational Materials Science
S. N. Bose National Centre for basic Sciences

Magnesium Alloy Design: A perspective on multi-scale modeling

: Dr. Amitava Moitra,
  Department of Chemical Engineering,
  The Pennsylvania State University

: Monday, September 17, 2012
: 4:00 PM
: Boson (LH-2)
: Magnesium Alloy Design: A perspective on multi-scale modeling

Abstract: We use generalized Peierls–Nabarro model to study the dislocation properties on the basal and prismatic planes in magnesium (Mg), for pure Mg and Mg with several alloying/solute elements. A multiscale modeling approach from first principles Density Functional Theory (DFT) calculation to directly link to the continuum scale modeling has been taken to design novel Mg-alloy. The DFT calculated generalized stacking fault energy (GSFE) curve enters the model to calculate continuum scale dislocation core width, stacking fault width, and Peierls stress. Solute effect on these GSFE has been calculated for nine alloying elements: Al, Ca, Ce, Gd, Li, Si, Sn, Zn, and Zr. Strength and ductility of these novel alloys can be qualitatively estimated with the dislocation properties. In light of the present calculations for the first time, an estimation has been brought up in order to increase the formability. This particular approach provides a design map for generation of novel materials.