Publications associées à Solute trapping-free massive transformation at absolute stability

A New Reference for the Thermal Equation of State of Iron

The high-pressure, high-temperature behavior of iron was investigated to 140 GPa and 3500 K with in situ synchrotron X-ray diffraction. Iron samples were compressed in diamond-anvil cells and heated up with the double-sided laser-heating system installed a ...

MDPI2020

Complements to Mugge and Friedel's Theory of Twinning

Cyril Cayron

The crystallography of twinning is based on the concepts of simple shear and obliquity introduced by Mugge, Mallard and Friedel at the turn of the last century, with tensor mathematics later developed by Bilby, Bevis and Crocker in the 1960s. We propose a ...

2020

Solidification of Metallic Alloys: Does the Structure of the Liquid Matter?

Michel Rappaz, Güven Kurtuldu

In 1952, Frank (Proc R Soc Lond Ser-Math Phys Sci 215:43-46, 1952) already postulated that Icosahedral Short Range Order (ISRO) of atoms in the liquid could possibly explain the large nucleation undercoolings measured in metallic alloys by Turnbull and Fis ...

SPRINGER2020

Design Study of a 50-kA React-and-Wind Bi-2212 Cable for Fusion Magnet

Davide Uglietti

In the last few years, the current density of Bi-2212 wires has been greatly improved by filament densify technologies. One further step toward applications in fusion magnets is to design a high current cable, which must overcome the drawbacks of Bi-2212 w ...

IEEE Institute of Electrical and Electronics Engineers2020

First principles study of the effect of hydrogen in austenitic stainless steels and high entropy alloys

William Curtin, Xiao Zhou

Hydrogen (H) embrittlement in multicomponent austenitic alloys is a serious limitation to their application in many environments. Recent experiments show that the High-Entropy Alloy (HEA) CoCrFeMnNi absorbs more H than 304 Stainless Steel but is less prone ...

2020

The interplay between deformation mechanisms in austenitic 304 steel during uniaxial and equibiaxial loading

Helena Van Swygenhoven, Efthymios Polatidis, Wei-Neng Hsu

The preferred deformation mechanisms with respect to the load path are studied in a medium stacking fault energy 304 austenitic stainless steel that exhibits both transformation induced plasticity and twinning induced plasticity. In situ neutron diffractio ...

2019

Variant selection in martensitic steels

Annick Pauline Baur

The martensitic phase transformation in steel is one of the most famous solid state transformation because of its contribution in the development of the modern industry. This transformation from a face-centered cubic (FCC) high temperature phase, called th ...

EPFL2019

On the chevron morphology of surface martensite

Roland Logé, Cyril Cayron, Annick Pauline Baur

It is established that the annealing twin boundaries of austenite act as nucleation sites for the martensitic transformation. In the present study, we observe that in surface martensite the transformation only takes place for twin boundaries that are appro ...

2019

A crystallographic extension to the Olson-Cohen model for predicting strain path dependence of martensitic transformation

Helena Van Swygenhoven, Efthymios Polatidis

A modification to the empirical Olson-Cohen strain-induced austenite to martensite transformation kinetic model is proposed. The proposed kinetic model accounts for the stress state at the grain level and the crystallography of the transformation mechanism ...

PERGAMON-ELSEVIER SCIENCE LTD2019

Deformation-induced martensitic transformation under multiaxial loading

Wei-Neng Hsu

The deformation-induced martensitic transformation observed in specific materials can enhance their mechanical properties or result in functional properties. For example, the transformation induced plasticity (TRIP) effect results in a good combination of ...

EPFL2019