UKAEA Papers

"Radiation-induced precipitation of chromium in Fe-Cr alloys containing C and N impurities: First-principles modelling and experimental observations"

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

Using exchange Monte Carlo (MC) simulations based on an ab initio-parameterized Cluster Expansion (CE) model, we explore the phase stability of low-Cr Fe-Cr alloys as a function of vacancy (Vac), carbon, and nitrogen interstitial impurity content. To parameterise the CE model, we perform density functional theory calculations for more than 1600 …

"Increasing the Adhesion of W to Si Substrates using Cr/Ti Interlayers"

• M. J. Lloyd
• C. Teoh
• G. Lim
• D. Nguyen-Manh
• D. Sobieraj
• J. S. Wrobel
• R. E. Simpson

The realisation of fusion energy depends on the development of advanced materials for challenging environments. Rapid screening of prototype alloys using magnetron sputtering and high throughput characterisation is currently being applied to candidate W alloys with improved mechanical performance, reduced activation and tolerance to damage from neu…

"An innovative materials design protocol for the development of novel refractory high-entropy alloys for extreme environments"

• O. El Atwani
• H.T. Vo
• M. Tunes
• C. Lee
• A. Alvarado
• N. Krienke
• J. Poplawsky
• A.A. Kohnert
• J. Gigax
• W.-Y. Chen
• M. Li
• Y. Wang
• J.S. Wróbel
• Duc Nguyen-Manh
• J.K.S. Baldwin
• U. Tukac
• E. Aydogan
• S. Fensin
• E. Martinez

In the quest of new materials that can withstand severe irradiation and mechanical extremes for advanced applications (e.g. fission reactors, fusion devices, space applications, etc), design, prediction and control of advanced materials beyond current material designs become a paramount goal. Here, though a combined experimental and simula…

"Thermodynamic Study of Hf Addition to Refractory Low-Activation W-Ta-Cr-V High Entropy Alloy from First-Principles"

• Andrew M. Alvarado
• Hi Vo Tin
• Jan S. Wr´obel
• Damian Sobieraj
• Duc Nguyen-Manh
• Saryu Jindal Fensin
• Enrique Martinez
• Osman El-Atwani

We present a Density Functional Theory-based cluster expansion model to predict the configurational energy of a multicomponent W-Ta-Cr-V-Hf quinary alloy. Coupled with Monte Carlo simulations we show that the model reproduces experimental observations. We analyze the thermodynamic properties of the W.31Ta.34Cr.05V.27Hf.03 system and observe two ph…

"Composition stability of single phase in Cr-Fe–Mn-Ni alloys at high temperature: First-principles prediction and experimental validation"

• Mark Fedorov
• Jan Wrobel
• Witold Chromińskia
• Grzegorz Cieślak
• Magdalena Płocińska
• Krzysztof J. Kurzydłowski
• Duc Nguyen-Manh

"Mechanical Characterisation of V-4Cr-4Ti Alloy: Tensile Tests Under High Energy Synchrotron Diffraction"

• Tay Sparks
• Duc Nguyen-Manh
• Pengfei Zheng
• Jan S. Wróbel
• Michael Gorley
• Thomas Connolley
• Christina Reinhard
• Yiqiang Wang
• Biao Cai

Vanadium base alloys represent potentially promising candidate structural materials for use in nuclear fusion reactors due to vanadium’s low activity, high thermal strength, and good swelling resistance. In this work, the mechanical properties of the current frontrunner vanadium base alloy, V-4Cr-4Ti, have been interrogated using in-situ high ene…

"Generalized Universal Equation of States for Magnetic Materials. Part II: Interatomic Potential development for Fe, validation and its predictability"

• Isaac Toda-Caraballoa
• 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 whic…

"Composition stability and Cr-rich phase formation in W-Cr-Y and W-Cr-Ti Smart Alloys"

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

W-Cr-Y smart alloys are potential material candidates for plasma facing components due to their protective behaviour during the loss-of-coolant accident (LOCA), while maintaining beneficial properties of W during the normal operation of the fusion power plant. During plasma exposure the lighter alloying elements are preferentially sputtered at t…

"First principles model for voids decorated by transmutation solutes: Short-range order effects and application to neutron irradiated tungsten"

• D. Nguyen-Manh
• J.S. Wrobel
• M. Klimenkov
• M.J. Lloyd
• L. Messina
• S.L. Dudarev

Understanding how properties of materials change due to nuclear transmutations is a major challenge for the design of structural components for a fusion power plant. In this study, by combining a first-principles matrix Hamiltonian approach with thermodynamic integration we investigate quasisteady state configurations of multi-component alloys, …

"Generalized Universal Equation of States for Magnetic Materials. Part I: A Formulation for Interatomic Potentials"

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

In this work, the Universal Equation of States (UES) is revisited and generalised by including ferromagnetic and antiferromagnetic configurations. The energy of a system is calculated by means of three parameters, namely, the energy, volume and corresponding scaling volume (directly related to the bulk modulus) at the local ground state of the corr…