Cyril Cayron

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

Shock-produced high-pressure (La, Ce, Th)PO4 polymorph revealed by microstructural phase heritage of monazite

The responses of uranium-bearing accessory minerals to shock metamorphism have received growing interest, because under extreme pressure and temperature conditions, these phases can form unique microstructures and/or polymorphs and their radiometric ages c ...

GEOLOGICAL SOC AMER, INC2019

Microstructures and Properties of Martensitic Materials

2019

Effect of powder characteristics and oxygen content on modifications to the microstructural topology during hot isostatic pressing of an austenitic steel

The effect of powder size distribution and oxygen content on the extent of multiple twinning and spatial distribution of oxide inclusions in hot isostatic pressed (HIPed) 316L steels was investigated using powders with different characteristics. Modificati ...

2019

Microstructural evolution and mechanical property development with nickel addition in low-carbon weld butt joints

Four metal powder flux-cored wires with added nickel (Ni) were designed to systematically investigate how Ni influences the microstructure and toughness in low-carbon bainitic weld metals (WMs). The microstructure was safely predicted by utilizing reasonab ...

2018

The relationship between low-temperature toughness and secondary crack in low-carbon bainitic weld metals

This paper aims to reveal the relationship among low-temperature toughness, microstructure and secondary crack from both microstructural and crystallographic perspectives. Instrumented Charpy tests were carried out in the upper platform, transition tempera ...

2018

Baddeleyite as a widespread and sensitive indicator of meteorite bombardment in planetary crusts

Cyril Cayron, Roland Logé

2018

Evidence of new twinning modes in magnesium questioning the shear paradigm

2018

Intricate morphologies of laths and blocks in low-carbon martensitic steels

2018

Shifting the Shear Paradigm in the Crystallographic Models of Displacive Transformations in Metals and Alloys

2018

Morphological and Crystallographic Characteristics of alpha Structure in a Low-Carbon Iron-Nickel Alloy

The features of a (body-centered cubic) structures were investigated in a low-carbon multicomponent alloy from morphological and crystallographic perspectives. In addition to apparent features of granular bainite and lamellar martensite, a morphological si ...

2018

Study on Bainite/Martensite Transformation in Reheated Weld Metals

A new combination of laser scanning confocal microscope (LSCM) and electron backscattering diffraction (EBSD) with a field-emission scanning electron microscope (SEM) is utilized to study the mechanism of bainite transformation in reheated low carbon baini ...

TRANS TECH PUBLICATIONS LTD2018

A one-step mechanism for new twinning modes in magnesium and titanium alloys modelled by the obliquity correction of a (58 degrees, a+2b) prototype stretch twin

The {11-22} and {11-26} twinning modes were recently discovered by Ostapovets et al. [Philos. Mag. (2017), 97, 1088-1101] and interpreted as {10-12}-{10-12} double twins formed by the simultaneous action of two twinning shears. Another interpretation is pr ...

Int Union Crystallography2018

Variant Selection in Fe-20Ni-1.8C under Bending

Variant selection is commonly observed in martensitic steels when a stress is applied to the material during transformation. Classically, the selection phenomenon is modelled considering the work of the shape strain in the applied stress field. This shape ...

2018

Microstructure tailoring of selenium-core multimaterial optoelectronic fibers

Cyril Cayron, Dang Tùng Nguyen, Fabien Sorin, Alexis Gérald Page, Wei Yan, Yunpeng Qu, Tapajyoti Dasgupta

The integration of semiconducting materials within thermally drawn multi-material polymer fibers is emerging as a versatile platform for flexible optoelectronics and advanced fabrics. Developing a deeper control over the microstructure of the electrically ...

Optical Society of America2017

Hard-sphere displacive model of extension twinning in magnesium

A crystallographic displacive model is proposed for the extension twins in magnesium. The atomic displacements are established, and the homogeneous lattice distortion is analytically expressed as a continuous angular-distortive matrix that becomes a shear ...

Elsevier Sci Ltd2017

Variant selection in surface martensite

A significant variant selection is reported in isothermal martensite formed on the surface of an Fe-30% Ni sample. The selection phenomenon is modelled using different descriptions of the martensitic phase transformation. In particular, matrices based on t ...

International Union of Crystallography2017

Evolution of grain boundary network topology in 316L austenitic stainless steel during powder hot isostatic pressing

The grain boundary network evolution of 316L austenitic steel powder during its densification by hot isostatic pressing (HIPing) was investigated. While the as-received powder contained a network of random high angle grain boundaries, the fully consolidate ...

2017

Cubic zirconia in >2370◦C impact melt records Earth’s hottest crust

Bolide impacts influence primordial evolution of planetary bodies because they can cause instantaneous melting and vaporization of both crust and impactors. Temperatures reached by impact-generated silicate melts are unknown because meteorite impacts are e ...

Elsevier2017

Hard-sphere displacive model of deformation twinning in hexagonal close-packed metals. Revisiting the case of the (56, a) contraction twins in magnesium