Seminar from Dr. Carlos N. TOMÉ


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Date | Time
24/09/2013 | All Day

Location
Salle Klepaczko

Categories


« Stress states associated with twin nucleation and propagation »

Dr. Carlos N. TOMÉ – Materials Science and Technology DivisionLos Alamos National Laboratory, Los Alamos, NM 87545, USA

Abstract Twinning plays a fundamental role in accommodating plastic deformation and explaining anisotropy and hardening of HCP materials. However, the stresses responsible for twin nucleation and propagation are still not well understood. This presentation is an attempt at discussing some key features and hopefully at throwing some light into the mechanisms responsible for twin activity in Mg and Zr.
Specifically, I will discuss the role played by grain boundaries, stress distributions at GB’s, and neighbor misorientation, upon twin nucleation and twin propagation. These features are implemented in a polycrystal model of nucleation. Local stress calculations in the vicinity of and inside twins are performed. Implications concerning nucleation, twin propagation and detwinning are discussed.