Publications related to Effect of post-heat treatment conditions on shape memory property in 4D printed Fe-17Mn-5Si-10Cr-4Ni shape memory alloy

Evaluation of Interface and Residual Strain of NiTi Layer Deposited on NiTiX Substrate by Laser Powder Bed Fusion

Elyas Ghafoori, Christian Leinenbach, Irene Ferretto, Mahbod Golrang, Mahshid Memarian

This study investigates the microstructure and properties of functionally graded NiTi alloy bilayers. The NiTi layer is printed by laser powder bed fusion on a NiTiX (where X is Hf or Cu) substrate prepared by vacuum arc remelting. Specimens produced with ...

Wiley-V C H Verlag Gmbh2024

Composition and Element Distribution Mapping of γ′ and γ" Phases of Inconel 718 by High-Resolution Scanning Transmission Electron Microscopy and X-ray Energy-Dispersive Spectrometry

Philippe Buffat

The main strengthening mechanism for Inconel 718 (IN718), a Ni-based superalloy, is precipitation hardening by gamma ' and gamma '' particles. It is thus essential, for good alloy performance, that precipitates with the desired chemical composition have ad ...

MDPI2024

Dislocation Hardening in a New Manufacturing Route of Ferritic Oxide Dispersion-Strengthened Fe-14Cr Cladding Tube

Roland Logé

The microstructure evolution associated with the cold forming sequence of an Fe-14Cr-1W-0.3Ti-0.3Y2O3 grade ferritic stainless steel strengthened by dispersion of nano oxides (ODS) was investigated. The material, initially hot extruded at 1100 degrees C an ...

MDPI2024

Electron-beam based nanoscale quantum controls

Hoda Shirzad

Advancing quantum technologies depends on the precise control of individual quantum systems, the so-called qubits, and the exploitation of their quantum properties. Nowadays, expanding the number of qubits to be entangled is at the core of the developments ...

EPFL2024

Microsecond Time-Resolved Cryo-Electron Microscopy

Oliver Florian Harder

Recently, single-particle cryo-electron microscopy emerged as a technique capable of determining protein structures at near-atomic resolution and resolving protein dynamics with a temporal resolution ranging from second to milliseconds. This thesis describ ...

EPFL2024

Fluorescence microscopy: A statistics-optics perspective

Aleksandra Radenovic

Fundamental properties of light unavoidably impose features on images collected using fluorescence microscopes. Accounting for these features is often critical in quantitatively interpreting microscopy images, especially those gathering information at scal ...

Amer Physical Soc2024

Solute-strengthening in metal alloys with short-range order

William Curtin, Shankha Nag

Recent surging interest in strengthening of High Entropy Alloys (HEAs) with possible chemical ordering motivates the development of new theory. Here, an existing theory for random alloys that accounts for solute-dislocation and solute–solute interactions i ...

2024

Revealing the Mechanism Underlying 3D-AFM Imaging of Suspended Structures by Experiments and Simulations

Marcos Penedo Garcia

The invention of 3D atomic force microscopy (3D-AFM) has enabled visualizing subnanoscale 3D hydration structures. Meanwhile, its applications to imaging flexible molecular chains have started to be experimentally explored. However, the validity and princi ...

Wiley-V C H Verlag Gmbh2024

Advances in High-Speed, Multiparametric Atomic Force Microscopy

Santiago Harald Andany

After decades of technological advancements, high-speed atomic force microscopy (HS-AFM) has emerged as a powerful technique for visualizing dynamic processes. At the nanoscale, the AFM provides valuable insights into the sample by sensing minute interacti ...

EPFL2024

Origin of the enhanced pseudo-elasticity of additively manufactured Fe-17Mn-5Si-4Ni-10Cr-(V, C) shape memory alloy fabricated by laser powder bed fusion

Christian Leinenbach, Irene Ferretto

This study investigated the origin of the enhanced pseudo-elasticity of additively manufactured vanadium carbide-containing Fe-based shape memory alloys. The aged samples with two different starting microstructures, as-built and solution-treated, showed co ...

Elsevier Science Sa2023

The influence of lattice misfit on screw and edge dislocation-controlled solid solution strengthening in Mo-Ti alloys

William Curtin, Carolina Baruffi, You Rao

Mo-Ti alloys form solid solutions over a wide range of compositions, with lattice misfit parameters increasing significantly with titanium content. This indicates a strong increase in the critical stress for edge dislocation motion. Here, we probe the tran ...

SPRINGERNATURE2023

Improved Waste Heat Management and Energy Integration in an Aluminum Annealing Continuous Furnace Using a Machine Learning Approach

François Maréchal, Manuele Gatti, Daniel Alexander Florez Orrego, Réginald Germanier, Mohammad Andayesh

Annealing furnaces are critical for achieving the desired material properties in the production of high-quality aluminum products. In addition, energy efficiency has become more and more important in industrial processes due to increasing decarbonization r ...

2023

In Situ and Time-Resolved Transmission Electron Microscopy of Nanoscale Processes

Chengcheng Yan

Observing the fast dynamics of nanoscale systems is crucial in order to understand and ultimately control their behavior. Characterizing these dynamic processes requires techniques with atomic spatial resolution and a temporal resolution that matches the t ...

EPFL2023

Heat transfer of uncoated and nanostructure coated commercially micro-enhanced refrigeration tubes under pool boiling conditions

John Richard Thome

The heat transfer performance of commercially produced micro-enhanced tubes with and without a nanocoating was investigated under pool boiling of saturated refrigerant. These multiscale enhancements were on the outside of 19 mm horizontal copper tubes heat ...

Pergamon-Elsevier Science Ltd2023

EBSD study of variant reorientation, texture, and twin formation in a martensitic NiTi alloy deformed in compression

Mathijs Pieter van der Meer, Cyril Cayron, Roland Logé, Junfeng Xiao

Martensitic crystallography plays a vital role in the texture evolution and mechanical properties in Nickel-Titanium (NiTi) shape memory alloys when subjected to deformation. However, their microstructural changes during deformation are not well known and ...

Pergamon-Elsevier Science Ltd2023

Phase Transformation-Induced Interfacial Debonding of Silica Inclusions in Iron

Andreas Mortensen, Alejandra Inés Slagter, David Hernandez Escobar, Julie Nathalie S Gheysen

We document that in unstressed, undeformed, samples of pure iron containing silica inclusions precipitated by melt deoxidation, the iron matrix and a small fraction of the silica inclusions are locally separated at room temperature by a void. Thermal cycli ...

Springer2023

Towards near-atomic resolution imaging of microsecond nanoscale dynamics

Gabriele Bongiovanni

Time-resolved electron microscopy has made significant progress in recent years, with some groups now working on instruments that offer attosecond temporal resolution. While much of the research in the field revolves around the improvement of temporal reso ...

EPFL2023

Effect of Mo addition on the mechanical and tribological properties of magnetron sputtered TiN films

Sami Rtimi

Ternary-based titanium nitride (TiN) thin films have drawn attention toward rational applications due to their wear resistance, high hardness, and corrosion resistance. The influence of Mo content on the structural, tribo-logical, and mechanical properties ...

ELSEVIER SCIENCE SA2023

Experimental study of the hydrodynamic and thermal performances of ventilated wall structures

Mohammad Rahiminejad, Dolaana Khovalyg

The presence of a ventilated air gap behind the external cladding in a building envelope is known to have a tangible contribution to the overall performance of the wall assembly. In the present study, the hydrodynamic and thermal performances of ventilated ...

2023

Thermal Design of a Medium Voltage Modular Multilevel Converter Cell

Drazen Dujic, Yanick Patrick Frei

This paper presents the cooling concept for a medium voltage modular multilevel converter cell. To optimize power density, the metallic enclosure is used to dissipate the heat generated by semiconductor losses, while maintaining maximum temperatures below ...

New York2023