UKAEA Papers

"Mobility of nano-sized 1⁄2⟨1 1 1⟩ vacancy and interstitial prismatic dislocation loops in tungsten"

• Jan Fikar
• Robin Schäublin
• Daniel R. Mason
• Duc Nguyen-Manh

The vacancies and interstitials produced in high-energy collision cascades of irradiated tungsten can form prismatic dislocation loops with Burgers vectors 1⁄2⟨1 1 1⟩ and ⟨1 0 0⟩. The 1⁄2⟨1 1 1⟩ loops are very mobile, and their mobility is essential for the microstructure development of irradiated materials, It is a key parameter …

"Unified generalized universal equation of states for magnetic Co, Cr, Fe, Mn and Ni: an approach for non-collinear atomistic modelling"

• I. Toda-Caraballo
• J. Wrobel
• D. Nguyen-Manh

Despite great efforts to study magnetic properties of 3d-transition metals from both fundamental and applied interest, there exists no modelling approach that would be able to describe magnetic and structural phase stability of all these elements on a unified formalism. In this work, we propose a qualitative improvement of the …

"A mesoscale phase-field model of intergranular liquid lithium corrosion of ferritic/martensitic steels"

• Alexandre Lhoest
• Sasa Kovacevic
• Duc Nguyen-Manh
• Joven Lim
• Emilio Martínez-Pañeda
• Mark R. Wenman1

A phase-field model is developed to simulate intergranular corrosion of ferritic/martensitic steels exposed to liquid lithium. The chromium concentration of the material is used to track the mass transport within the metal and liquid (corrosive) phase. The framework naturally captures intergranular corrosion by enhancing the diffusion of chromiu…

"Segregation, ordering, and precipitation in WTaV-based concentrated refractory alloys"

• Jesper Byggmästar
• Damian Sobieraj
• Jan S. Wróbel
• Daniel K. Schreiber
• Osman El-Atwani
• Enrique Martinez
• Duc Nguyen-Manh

Tungsten-based low-activation high-entropy alloys are possible candidates for next-generation fusion reactors due to their exceptional tolerance to irradiation, thermal loads, and stress. We develop an accurate and efficient machine-learned interatomic potential for the W–Ta–Cr–V system and use it in hybrid Monte Carlo mo…

"Thermodynamic Assessment of the Quaternary WTaCrV Refractory High Entropy Alloy as a Means to Guide Experimental Approaches"

• Bochuan Sun
• Mark Fedorov
• Jan Wrobel
• Duc Nguyen-Manh
• Caleb Hatler
• Matthew Vigil
• Dan J. Thoma
• Osman El-Atwani
• Enrique Martinez

High-entropy alloys (HEAs) are being explored as potential candidates for radiation-tolerant materials, with some compositions exhibiting good resistance to defect cluster formation. One such system is WTaCrV, although only a single composition has been experimentally tested under ion irradiation, where it showed phase decomposition at low temperat…

"Generalized universal equation of states for magnetic materials: A novel formulation for an interatomic potential in Fe"

• Isaac Toda-Caraballo
• Jan S. Wróbel
• Duc Nguyen-Manh

The development of quantitative models for understanding physical properties of alloys requires a proper treatment of magnetic interactions, which is of paramount importance for the microstructural stability, especially in steels and high-entropy alloys containing magnetic elements. These magnetic interactions also control the defects behavior w…

"Microstructural evolution and transmutation in tungsten under ion and neutron irradiation"

• Matthew J Lloyd
• Jack Haley
• Bethany Jim
• Robert Abernethy
• Mark R Gilbert
• Enrique Martinez
• Khalid Hattar
• Osman El-Atwani
• Duc Nguyen-Manh
• Michael P Moody
• Paul A.J. Bagot
• David E.J. Armstrong

This study aims to compare the effects of neutron and self-ion irradiation on the mechanical properties and microstructural evolution in W. Neutron irradiation at the HFR reactor to 1.67 dpa at 800 ◦C resulted in the formation of large Re and Os rich clusters and voids. The post-irradiation composition was measured using APT and verfified against…

"Precipitation of Cr-rich clusters in Fe-Cr alloys: Effects of irradiation from first principles modeling and experimental observations"

• Mark Fedorov
• Jan S. Wróbel
• Andrew J. London
• Krzysztof J. Kurzydłowski
• Chu-Chun Fu
• Tonˇci Tadi´
• Sergei L. Dudarev
• Duc Nguyen-Manh

"Co-segregation of Y and Zr in W-Cr-Y-Zr alloys: First-principles modeling at finite temperature and application to SMART materials"

• Damian Sobieraj
• Jan S. Wróbel
• Mark R. Gilbert
• Krzysztof J. Kurzydłowski
• Duc Nguyen-Manh

Spinodal phase separation in SMART (Self-passivating Metal Alloys with Reduced Thermo-oxidation) materials based on binary W-Cr with alloying elements Y and Zr is systematically investigated by a combination of Density Functional Theory with Cluster Expansion Hamiltonian and large-scale Monte Carlo simulations with thermodynamic integration. Compar…

"An Atomic Cluster Expansion interatomic potential for lithium: investigating the solid and liquid phases"

• P. Srinivasan
• M. R. Gilbert
• S. Puri
• K. P. Dominguez
• A. Horsfield
• D. Nguyen-Manh

We develop an atomic cluster expansion (ACE) interatomic potential for lithium that accurately models both the solid and liquid phase and the corresponding melting point. The predicted properties for both phases are in close agreement with density functional theory (DFT) and experimental data from literature. The potential is able to capture the…