Publications associées à Solute strengthening in random alloys

Solute-strengthening in metal alloys with short-range order

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

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

First-principles thermodynamics of precipitation in aluminum-containing refractory alloys

Anirudh Raju Natarajan

Materials for high -temperature environments are actively being investigated for deployment in aerospace and nuclear applications. This study uses computational approaches to unravel the crystallography and thermodynamics of a promising class of refractory ...

Pergamon-Elsevier Science Ltd2024

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

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

Modeling of precipitate strengthening with near-chemical accuracy: case study of Al-6xxx alloys

William Curtin, Yi Hu

Many metal alloys are strengthened by controlling precipitation to achieve an optimal peak-aged condi-tion where the strength-limiting processes of precipitate shearing and Orowan looping are thought to be comparable. Qualitative models have long captured ...

PERGAMON-ELSEVIER SCIENCE LTD2022

Screw vs. edge dislocation strengthening in body-centered-cubic high entrophy alloys and implications for guided alloy design

William Curtin, Francesco Maresca, Carolina Baruffi

Body-centered-cubic (BCC) high entropy alloys (HEAs) can show exceptionally high strength up to high temperatures. Mechanistic theories are needed to guide alloy discovery within the immense multicomponent HEA compositional space. Here, two new theories fo ...

SPRINGER HEIDELBERG2022

Machine learning for metallurgy IV: A neural network potential for Al-Cu-Mg and Al-Cu-Mg-Zn

William Curtin, Daniel John Gilles Marchand

Most metallurgical properties, e.g., dislocation propagation, precipitate formation, can only be fully understood atomistically but most phenomena and quantities of interest cannot be measured experimentally. Accurate simulation methods are essential but f ...

2022

Strengthening mechanisms in dilute and random solid solution high-entropy BCC alloys

Alireza Ghafarollahi

Tuning the mechanical properties of metals, including strength, through adjusting the type and/or concentration of added solute elements, has been recognized as an effective way to design and produce materials with desired or optimized mechanical propertie ...

EPFL2022

Effect of Y2O3 dispersoids on microstructure and creep properties of Hastelloy X processed by laser powder-bed fusion

Christian Leinenbach

Laser powder bed fusion (LPBF) was used to consolidate powders of a Ni-Cr-Fe-Mo alloy (Hastelloy X) blended with 1 wt% Y2O3 nanometric powders. The nearly-dense, crack-free specimens, with and without oxide dispersion strengthening (ODS), exhibit high-aspe ...

ELSEVIER2022

Development of High-Strength Aluminum Alloys for Additive Manufacturing

Marvin Lennard Schuster

Metal additive manufacturing (AM) offers the possibility to rapidly produce complex geometries that are not achievable with conventional manufacturing methods. The two most common technologies, Laser Powder Bed Fusion (LPBF) and Direct Metal Deposition (DM ...

EPFL2022

Processability, microstructure and precipitation of a Zr-modified 2618 aluminium alloy fabricated by laser powder bed fusion

Christian Leinenbach, Xavier Maeder

Additive manufacturing offers the opportunity to produce complex geometries from novel alloys with improved properties. Adapting conventional alloys to the process-specific properties can facilitate rapid implementation of these materials in industrial pra ...

2022

Neural Network Potentials for Age Hardening Aluminum Alloys

Daniel John Gilles Marchand

High-strength metal alloys achieve their performance via careful control of precipitates and solutes. The nucleation, growth, and kinetics of precipitation, and the resulting mechanical properties, are inherently atomic scale phenomena, particularly during ...

EPFL2022

Micro-addition of Fe in highly alloyed Cu-Ti alloys to improve both formability and strength

Cyril Cayron, Roland Logé, Baptiste Thomas Jean Rouxel

Cu-Be alloys provide excellent electrical and mechanical properties, but present serious health hazards during manufacturing. Among alternative alloys, the Cu-Ti system has the highest yield strength; however, Ti cannot be easily solutionized at concentrat ...

ELSEVIER SCI LTD2022

Precipitation Strengthening in Al-Mg-Si Alloys

Yi Hu

Precipitation strengthening is one of the key strengthening strategies in many industrial alloys like aluminum alloys, nickel-based superalloys, etc. The yield strength of alloy is improved by forming precipitates in materials and employing them as obstacl ...

EPFL2021

Modeling peak-aged precipitate strengthening in Al–Mg–Si alloys

William Curtin, Yi Hu

Strengthening by needle-shaped precipitates is critical in Al–Mg–Si alloys. Here, the strengthening is studied computationally at the peak-aged condition where precipitate shearing and Orowan looping are usually considered to have equal strengths. Pseudo-r ...

2021

Laser powder-bed fusion of metallic alloys with enhanced microstructures and properties

Navid Sohrabi

Laser powder-bed fusion (LPBF) is an additive manufacturing (AM) process that uses a laser to selectively melt a powder bed. This process can build dense samples with complicated geometries from a wide variety of metallic alloys. In this thesis, LPBF of al ...

EPFL2021

Atomic scale investigations of fracture in metal alloys

Eleanor Yi Kei Mak

The demand for metal alloys with superior structural performance in industrial applications continues to increase, as does the need for more-energy efficient materials and methods. Many materials that are otherwise attractive for structural applications ar ...

EPFL2021

Development of Mechanical Strengthening System for Bridge Connections Using Prestressed CFRP Rods

Alain Nussbaumer, Elyas Ghafoori, Masoud Motavalli, Hossein Heydarinouri

Stringer-to-floor beam web-to-web double-angle connections are among the most fatigue-prone elements in old riveted bridges. These connections are often designed to carry only shear loads. However, in these elements, fatigue damage occurs because of the ou ...

ASCE-AMER SOC CIVIL ENGINEERS2021

Strengthening of Steel Connections in a 92-Year-Old Railway Bridge Using Prestressed CFRP Rods: Multiaxial Fatigue Design Criterion

Alain Nussbaumer, Elyas Ghafoori, Masoud Motavalli, Hossein Heydarinouri

This paper presented a new retrofit system for strengthening the stringer-to-floor-beam double-angle connections in a 92-year-old riveted railway bridge in Switzerland, using prestressed carbon fiber-reinforced polymer (CFRP) rods. The strengthening system ...

ASCE-AMER SOC CIVIL ENGINEERS2021