PROBIEN   20416
INSTITUTO DE INVESTIGACION Y DESARROLLO EN INGENIERIA DE PROCESOS, BIOTECNOLOGIA Y ENERGIAS ALTERNATIVAS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Simulations of the effects of hydrogen on the tensile properties of palladium
Autor/es:
M. RUDA; E. CRESPO; S. RAMOS; E. BRINGA; F. BRASCHI; M.L. ALÍ
Lugar:
San Pablo
Reunión:
Conferencia; ABM - TMS Second Pan American Materials Conference; 2014
Institución organizadora:
Asociación Brasilero de Materiales
Resumen:
The
Pd-H system is of great technological interest in relation to H storage and purification
applications, as well as catalysis. In this work molecular dynamics (MD)
atomistic simulations of uniaxial tensile deformation have been performed on
single crystal and nano-polycrystalline Pd samples at room temperature (300 K)
with different concentrations of H. The polycrystalline samples consisted on
columnar grains randomly oriented of average grain sizes ranging from 5-20 nm.
Interatomic potentials of the Embedded-Atom (EAM) type were used to
describe the interactions among atoms. The H absorption
process was modeled at the atomistic scale by Monte Carlo simulations in the TPmuN ensemble.
For mono-crystalline Pd in the alpha phase, stress-strain curves showed
decreasing elastic moduli and yield strength with increasing H concentration.
At low H concentrations in the polycrystalline samples, H agglomerated at grain
boundaries, anchoring them and stopping the grain growth which would occur
under tension in samples without H. At high H concentrations (beta
phase) homogeneous hydride formation was observed