Publications de Mario Alberto Salgado Ordorica

Morphology and Growth Kinetic Advantage of Quenched Twinned Dendrites in Al-Zn Alloys

Michel Rappaz, André Phillion, Mario Alberto Salgado Ordorica

Twinned dendrites appearing in an Al-26 wt pct Zn alloy have been quenched during growth using a specifically designed setup that is positioned on top of a directional solidification experiment. X-ray tomography performed at the Swiss Light Source (SLS-bea ...

Springer Verlag2013

Study of the twinned dendrite tip shape I : Phase-field modeling

Michel Rappaz, Jean-Luc Desbiolles, Mario Alberto Salgado Ordorica

The growth kinetics advantage of twinned aluminum dendrites over regular ones is still an unsolved problem of solidification. Although it is linked to the tip geometry, the influence of a coherent (1 1 1) twin plane on a < 1 1 0 > twinned dendrite tip is u ...

Elsevier2011

Study of the twinned dendrite tip shape II: Experimental assessment

Michel Rappaz, Marco Cantoni, Pierre Burdet, Mario Alberto Salgado Ordorica

The favorable growth kinetics of twinned dendrites can be explained by their complex morphology, multiple side branching mechanisms, growth undercooling and tip morphology. Three models were proposed for the twinned dendrite tip shape: (i) a grooved tip sa ...

2011

The influence of solid-liquid interfacial energy anisotropy on equilibrium shapes, nucleation, triple lines and growth morphologies

Michel Rappaz, Mario Alberto Salgado Ordorica, Jonathan Friedli, Aurèle Mariaux

The anisotropy of the solid-liquid interfacial energy plays a key role during the formation of as-solidified microstructures. Using the xi-vector formalism of Cahn and Hoffman, this contribution presents the effect that anisotropy has on the equilibrium sh ...

Elsevier2010

Characterization and modeling of twinned dendrite growth

Mario Alberto Salgado Ordorica

The formation of feathery grains during semi-continuous casting of Al-alloys [1, 2] is an interesting problem from both practical and theoretical points of view. These structures are formed by a lamellar sequence of twinned and untwinned regions separated ...

EPFL2009

Phase Field Modelling Of Twinned Dendrite Growth

Michel Rappaz, Jean-Luc Desbiolles, Mario Alberto Salgado Ordorica

Twinned dendrite growth has been found to occur in aluminum alloys when critical thermal conditions (G approximate to 100 K/cm, nu(s) approximate to 1 mm/s) and a slight convection in the melt are present during directional solidification. Split in their t ...

Minerals, Metals & Materials Soc, 184 Thorn Hill Rd, Warrendale, Pa 15086-7514 Usa2009

EBSD: a powerful microstructure analysis technique in the field of solidification

Michel Rappaz, Emmanuelle Boehm Courjault, Alain Jacot, Mario Alberto Salgado Ordorica, Aurèle Mariaux, Christoph Niederberger

This paper presents a few examples of the application of electron back-scatter diffraction (EBSD) to solidification problems. For directionally solidified Al-Zn samples, this technique could reveal the change in dendrite growth directions from < 100 > to < ...

2009

Study of twinned dendrite growth stability

Michel Rappaz, Jonas Valloton, Mario Alberto Salgado Ordorica

Under certain thermal conditions (G approximate to 1 x 10(4) K/m, v(s) approximate to 1 x 10(-3) m/s), < 1 1 0 > twinned dendrites appear in aluminum alloys and can overgrow regular columnar dendrites, provided that some convection is also present in the m ...

Elsevier2009

Twinned dendrite growth in binary aluminum alloys

Michel Rappaz, Mario Alberto Salgado Ordorica

The formation of twinned dendrites (feathery grains) in binary Al-Zn, Al-Mg, Al-Cu and Al-Ni alloys has been studied in specimens directionally solidified under identical thermal conditions, i.e. G approximate to 100 K cm(-1), v approximate to 1 mm s(-1), ...

Elsevier2008