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On ice mechanics in ice-induced vibrations

Owen, C.C. (author)

The imminence of anthropogenic climate change has motivated a global energy transition towards sustainable power generation. Offshore wind—an important contributor to the energy transition—is expanding, not only in turbine size and number of installations, but also into regions with harsher environmental conditions. One of those conditions in...

doctoral thesis 2024

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Unravelling microstructure-electroactivity relationships in free-standing polycrystalline boron-doped diamond: A mapping study

Liu, Z. (author), Baluchová, S. (author), Li, Z. (author), Gonzalez Garcia, Y. (author), Hall, Clive E. (author), Buijnsters, J.G. (author)

In this work, four different techniques were concurrently applied to study the interplay between local electroactivity and electrode surface characteristics of free-standing, polycrystalline boron-doped diamond (BDD). Scanning electron microscopy, electron back-scatter diffraction, Raman mapping and scanning electrochemical microscopy were...

journal article 2024

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Incompatibility stress at inclined grain boundaries for cubic crystals under hydrostatic stress and uniaxial stress

Liu, K. (author), Sluiter, M.H.F. (author)

In a material under stress, grain boundaries may give rise to stress discontinuities. The stress state at grain boundaries strongly affects microscopic processes, such as diffusion and segregation, as well as failure initiation, such as fatigue, creep, and corrosion. Here the general condition of incompatibility stress at grain boundaries is...

journal article 2024

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Effects of Grain Boundaries and Surfaces on Electronic and Mechanical Properties of Solid Electrolytes

Xie, Weihang (author), Deng, Zeyu (author), Liu, Zhengyu (author), Famprikis, T. (author), Butler, Keith T. (author), Canepa, Pieremanuele (author)

Extended defects, including exposed surfaces and grain boundaries (GBs), are critical to the properties of polycrystalline solid electrolytes in all-solid-state batteries (ASSBs). These defects can alter the mechanical and electronic properties of solid electrolytes, with direct manifestations in the performance of ASSBs. Here, by building a...

journal article 2024

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Effect of stacking fault energy on the thickness and density of annealing twins in recrystallized FCC medium and high-entropy alloys

Schneider, Mike (author), Couzinié, Jean Philippe (author), Shalabi, Amin (author), Ibrahimkhel, Farhad (author), Ferrari, A. (author), Körmann, F.H.W. (author), Laplanche, Guillaume (author)

This work aims to predict the microstructure of recrystallized medium and high-entropy alloys (MEAs and HEAs) with a face-centered cubic structure, in particular the density of annealing twins and their thickness. Eight MEAs and five HEAs from the Cr-Mn-Fe-Co-Ni system are considered, which have been cast, homogenized, cold-worked and...

journal article 2024

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Novel Austenisation Procedure for Quenched and Tempered 51CrV4 Spring Steel: Investigating the effect of grain boundary embrittlement and shot-peening on fatigue life

Meisters, Thomas (author)

VDL Weweler has developed a novel heat treatment approach for their trailing arms, which eliminates the traditional austenisation step and instead capitalises on the inherent heat used for hot-forming to austenise the steel before quenching. This not only saves energy, but surprisingly also improves the lifetime of the products. The underlying...

master thesis 2023

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Compositive role of refractory element Mo in improving strength and ductility of face-centered-cubic complex concentrated alloys

Jang, Tae Jin (author), Lee, You Na (author), Ikeda, Yuji (author), Körmann, F.H.W. (author), Baek, Ju Hyun (author), Do, Hyeon Seok (author), Choi, Yeon Taek (author), Gwon, Hojun (author), Suh, Jin Yoo (author), Kim, Hyoung Seop (author), Lee, Byeong Joo (author), Zargaran, Alireza (author), Sohn, Seok Su (author)

Complex concentrated alloys (CCAs) with a face-centered-cubic (FCC) structure exhibit remarkable mechanical properties, introducing the expansion of compositional space in alloy design for structural materials. The formation of a single solid-solution phase is enabled by configuring various 3d-transition elements, while doping other elements...

journal article 2023

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Stresses at grain boundaries: The maximum incompatibility stress in an infinitely extended elastic bicrystal under uniaxial loading

Liu, K. (author), Sluiter, M.H.F. (author)

In a material under stress, grain boundaries may give rise to stress discontinuities. Stress localization is crucial to materials' behavior such as segregation, precipitation, and void nucleation. Here, the stress state at a grain boundary perpendicular to a uniaxial external stress is studied systematically. The grain boundary with the most...

journal article 2023

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An initial study of interference coloration for quantifying the texture and fabric of ice

Owen, C.C. (author), Hendrikse, H. (author)

The manual application of universal (Rigsby) stage techniques is commonly used to determine the fabric of thin sections of ice viewed with crossed-polarized light. This process can require hours of focus in cold conditions to identify the c-axis of each grain in a thin section. Automated ice texture and fabric methods of several forms exist...

journal article 2023

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Dislocation pileups in small grains

Schouwenaars, R. (author), Kestens, L.A.I. (author)

While the grain size effect (GSE) is universally observed in polycrystalline metals and alloys, extended dislocation pileups (DPUs) at grain boundaries (GBs) are rarely observed. Although this discrepancy was noticed over 50 years ago, DPUs are still widely accepted as the explanation for the GSE, often expressed as the Hall-Petch (HP)...

journal article 2023

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Roles of the grain-boundary characteristics and distributions on hydrogen embrittlement in face-centered cubic medium-entropy V_xCr_1-xCoNi alloys

Yang, Dae Cheol (author), Song, Sang Yoon (author), Kim, Han Jin (author), Lee, Sang In (author), Dutta, B. (author), Kim, Young Kyun (author), Shim, Jae Hyeok (author), Suh, Jin Yoo (author), Na, Young Sang (author), Sohn, Seok Su (author)

The issue of hydrogen embrittlement (HE) in face-centered (FCC) structured alloys is significant for H storage and transportation application due to unanticipated damage beyond its predicted service life. This unpredictable situation may harm human life and limit hydrogen to a reliable source of renewable energy in industrial fields. Recent...

journal article 2023

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Tailoring precipitation/properties and related mechanisms for a high-strength aluminum alloy plate via low-temperature retrogression and re-aging processes

Hou, L. G. (author), Yu, H. (author), Wang, Y. W. (author), You, L. (author), He, Z. B. (author), Wu, C. M. (author), Eskin, D. G. (author), Katgerman, L. (author), Zhuang, L. Z. (author), Zhang, J. S. (author)

The retrogression and re-aging (RRA) processes, aimed mainly at tailoring intergranular precipitates, could significantly improve the corrosion resistance (i.e., stress corrosion cracking resistance) without considerably decreasing the strength, which signifies that an efficient control of the size, distribution and evolution of intergranular...

journal article 2022

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Effects of temperature and grain size on diffusivity of aluminium: electromigration experiment and molecular dynamic simulation

Cui, Z. (author), Zhang, Y. (author), Hu, D. (author), Vollebregt, S. (author), Fan, J. (author), Fan, X. (author), Zhang, Kouchi (author)

Understanding the atomic diffusion features in metallic material is significant to explain the diffusion-controlled physical processes. In this paper, using electromigration experiments and molecular dynamic (MD) simulations, we investigate the effects of grain size and temperature on the self-diffusion of polycrystalline aluminium (Al). The...

journal article 2022

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Perovskite solar cells with embedded homojunction via nonuniform metal ion doping

Lin, Yuze (author), Li, Tao (author), Liu, Ye (author), Bahrami, Behzad (author), Guo, Dengyang (author), Fang, Yanjun (author), Shao, Yuchuan (author), Wang, Qi (author), Savenije, T.J. (author)

A long photoluminescence decay lifetime has been regarded as a generic indication of long charge carrier recombination lifetime in semiconductors such as metal halide perovskites (MHPs), which have shown tremendous success in solar cells. Here, we report that MHP polycrystalline films with extrinsic metal ions have a very long charge...

journal article 2021

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The role of grain-boundary cementite in bainite formation in high-carbon steels

Ravi, A.M. (author), Sietsma, J. (author), Santofimia, Maria Jesus (author)

Low temperature bainite formation in high-carbon steels leads to highly refined microstructures. However, the rate of bainite formation becomes impractically low as the bainite formation temperature decreases. Thus, it is important to create strategies to accelerate the low-temperature bainite formation kinetics in high-carbon steels. In this...

journal article 2020

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Mechanical Response of Nanocrystalline Ice-Contained Methane Hydrates: Key Role of Water Ice

Cao, Pinqiang (author), Ning, Fulong (author), Wu, Jianyang (author), Cao, Boxiao (author), Li, Tianshu (author), Sveinsson, Henrik Andersen (author), Liu, Z. (author), Vlugt, T.J.H. (author), Hyodo, Masayuki (author)

Water ice and gas hydrates can coexist in the permafrost and polar regions on Earth and in the universe. However, the role of ice in the mechanical response of ice-contained methane hydrates is still unclear. Here, we conduct direct million-atom molecular simulations of ice-contained polycrystalline methane hydrates and identify a crossover...

journal article 2020

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Positron Annihilation Studies on Thin Film Solar Cells: CdSe and PbSe Quantum Dot Thin Films and Cu(In1-xGax)Se2 Layered Systems

Shi, W. (author)

High efficiency, low cost, and long stability are three key factors for the wide application of photovoltaics (PV) which are currently intensively studied in order to meet the increasing global renewable energy demand. Currently, the PV market is mainly based on silicon. However, solar cells based on silicon may not be capable to meet the long...

doctoral thesis 2019

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Modelling of Grain Boundary Segregation for Nanocrystalline Alloys: Applied to Pd-based Alloys

Liu, Xiaoyezi (author)

The Pd-based metal membranes have been focused on many studies, because they are the most promising candidates for hydrogen separation. If Pd-based membranes are designed in nanoscale, then the introduced high volume fraction of grain boundaries can act as fast diffusion paths for hydrogen atoms that leading to an increase of hydrogen separation...

master thesis 2018

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Evolution and role of vacancy clusters at grain boundaries of ZnO:Al during accelerated degradation of Cu(In, Ga)Se2 solar cells revealed by positron annihilation

Shi, W. (author), Theelen, Mirjam (author), Illiberi, Andrea (author), van der Sar, S.J. (author), Butterling, M. (author), Schut, H. (author), Zeman, M. (author), Brück, E.H. (author), Eijt, S.W.H. (author)

Positron annihilation lifetime spectroscopy (PALS) and Doppler broadening positron annihilation spectroscopy (DB-PAS) depth profiling demonstrate pronounced growth of vacancy clusters at the grain boundaries of as-deposited Al-doped ZnO films deposited as transparent conductive oxide (TCO) on Cu(In,Ga)Se2 (CIGS) solar cells upon accelerated...

journal article 2018

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Evolution and role of vacancy clusters at grain boundaries of ZnO:Al during accelerated degradation of Cu(In, Ga)Se-2 solar cells revealed by positron annihilation

Shi, W. (author), Theelen, Mirjam (author), Illiberi, Andrea (author), van der Sar, S.J. (author), Butterling, M. (author), Schut, H. (author), Zeman, M. (author), Brück, E.H. (author), Eijt, S.W.H. (author)

Positron annihilation lifetime spectroscopy (PALS) and Doppler broadening positron annihilation spectroscopy DB-PAS) depth profiling demonstrate pronounced growth of vacancy clusters at the grain boundaries of as-deposited Al-doped ZnO films deposited as transparent conductive oxide (TCO) on Cu(In, Ga)Se2 (CIGS) solar cells upon accelerated...

journal article 2018