Logo: to the web site of Uppsala University

uu.sePublications from Uppsala University
Change search
Link to record
Permanent link

Direct link
Publications (10 of 23) Show all publications
Fritze, S., Hahn, R., Aboulfadl, H., Johansson, F. O. .., Lindblad, R., Böör, K., . . . Thuvander, M. (2024). Elemental distribution and fracture properties of magnetron sputtered carbon supersaturated tungsten films. Surface & Coatings Technology, 477, Article ID 130326.
Open this publication in new window or tab >>Elemental distribution and fracture properties of magnetron sputtered carbon supersaturated tungsten films
Show others...
2024 (English)In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 477, article id 130326Article in journal (Refereed) Published
Abstract [en]

The combination of strength and toughness is a major driving force for alloy design of protective coatings, and nanocrystalline tungsten (W)-alloys have shown to be promising candidates for combining strength and toughness. Here we investigate the elemental distribution and the fracture toughness of carbon (C) alloyed W thin films prepared by non-reactive magnetron sputtering. W:C films with up to ~4 at.% C crystallize in a body-centered-cubic structure with a strong 〈hh0〉texture, and no additional carbide phases are observed in the diffraction pattern. Atom probe tomography and X-ray photoelectron spectroscopy confirmed the formation of such a supersaturated solid solution. The pure W film has a hardness ~13 GPa and the W:C films exhibit a peak hardness of ~24 GPa. In-situ micromechanical cantilever bending tests show that the fracture toughness decreases from ~4.5 MPa·m1/2 for the W film to ~3.1 MPa·m1/2 for W:C films. The results show that C can significantly enhance the hardness of W thin films while retaining a high fracture toughness.

Place, publisher, year, edition, pages
Elsevier, 2024
Keywords
PVD, Fracture toughness, Atom probe tomography, XPS, Tungsten
National Category
Inorganic Chemistry
Identifiers
urn:nbn:se:uu:diva-521828 (URN)10.1016/j.surfcoat.2023.130326 (DOI)001149676000001 ()
Funder
Swedish Foundation for Strategic Research, RMA15-0048
Available from: 2024-01-29 Created: 2024-01-29 Last updated: 2024-02-15Bibliographically approved
Osinger, B., Donzel-Gargand, O., Fritze, S., Jansson, U. & Lewin, E. (2024). Structural and mechanical properties of magnetron sputtered (NbxMo1-x)C thin films. Vacuum, 224, Article ID 113146.
Open this publication in new window or tab >>Structural and mechanical properties of magnetron sputtered (NbxMo1-x)C thin films
Show others...
2024 (English)In: Vacuum, ISSN 0042-207X, E-ISSN 1879-2715, Vol. 224, article id 113146Article in journal (Refereed) Published
Abstract [en]

While transition metal carbides (TMCs) exhibit favourable mechanical properties, alloying according to the valence electron concentration (VEC) has the potential to further enhance the properties of these hard but inherently brittle materials. This study investigates the influence of alloying on the microstructure and mechanical properties of (NbxMo1-x)C carbide films, including binary references and ternary compositions with varying metal ratios (x between 0.35 and 0.53). Furthermore, the influence of various substrate materials is studied by comparing films deposited on Al2O3, MgO and SiO2. All films exhibit a NaCl-type carbide structure and X-ray photoelectron spectroscopy revealed the presence of small amounts of an additional amorphous carbon (a-C) phase. Hardness values around 20 ± 2 GPa were obtained for the films on Al2O3 and MgO, whereas a reduced hardness of 11 ± 1 GPa was observed for the films on SiO2 which is attributed to larger crystallite size and more polycrystalline structure. Overall no clear trend as a function of composition can be noted, indicating that microstructure effects dominate the mechanical properties in this study overshadowing the effect of varying the metal content.

Place, publisher, year, edition, pages
Elsevier, 2024
Keywords
Magnetron sputtering, Ceramic coating, Transition metal carbides, Mechanical properties
National Category
Materials Chemistry
Research subject
Chemistry with specialization in Materials Chemistry
Identifiers
urn:nbn:se:uu:diva-517298 (URN)10.1016/j.vacuum.2024.113146 (DOI)001218592400001 ()
Funder
Swedish Research Council, 2018-04834Swedish Research Council, 2017-00646_9Swedish Foundation for Strategic Research, RIF14-0053
Available from: 2024-01-09 Created: 2024-01-09 Last updated: 2024-05-31Bibliographically approved
Tunes, M. A., Fritze, S., Osinger, B., Willenshofer, P., Alvarado, A. M., Martinez, E., . . . El-Atwani, O. (2023). From high-entropy alloys to high-entropy ceramics: The radiation-resistant highly concentrated refractory carbide (CrNbTaTiW)C. Acta Materialia, 250, Article ID 118856.
Open this publication in new window or tab >>From high-entropy alloys to high-entropy ceramics: The radiation-resistant highly concentrated refractory carbide (CrNbTaTiW)C
Show others...
2023 (English)In: Acta Materialia, ISSN 1359-6454, E-ISSN 1873-2453, Vol. 250, article id 118856Article in journal (Refereed) Published
Abstract [en]

High-entropy materials represent the state-of-the-art on the alloy design strategy for future applications in extreme environments. Recent data indicates that high-entropy alloys (HEAs) exhibit outstanding radiation resistance in face of existing diluted alloy counterparts due to suppressed damage formation and evolution. An extension of the HEA concept is presented in this paper towards the synthesis and characterization of novel high-entropy ceramics as emergent materials for application in environments where energetic particle irradiation is a major concern. A novel carbide within the quinary refractory system CrNbTaTiW has been synthesized using magnetron-sputtering. The material exhibited nanocrystalline grains, single-phase crystal structure and C content around 50 at.%. Heavy-ion irradiation with in-situ Transmission Electron Microscopy was used to assess the irradiation response of the new high-entropy carbide (HEC) at 573 K and a comparison with the HEA within the system is made. No displacement damage effects appear within the microstructures of both HEA and HEC up to a dose of 10 displacements-per-atom. Surprisingly, the HEC has not amorphized under the investigated conditions. Xe was implanted in both materials and bubbles nucleated, but smaller sizes compared with conventional nuclear materials shedding light they are potential candidates for use in nuclear energy.

Place, publisher, year, edition, pages
Elsevier, 2023
Keywords
High-entropy ceramics, High-entropy alloys, Nanocrystalline materials, Radiation damage, Extreme environments
National Category
Materials Engineering
Identifiers
urn:nbn:se:uu:diva-499313 (URN)10.1016/j.actamat.2023.118856 (DOI)000958714700001 ()
Funder
EU, European Research Council, 757961Swedish Research Council, 2017-00646_9Swedish Research Council, 2019_00191Swedish Foundation for Strategic Research, RIF14-0053
Available from: 2023-03-27 Created: 2023-03-27 Last updated: 2024-01-11Bibliographically approved
Kaplan, M., Srinath, A., Riekehr, L., Nyholm, L., Hjörvarsson, B. & Fritze, S. (2022). Combinatorial design of amorphous TaNiSiC thin films with enhanced hardness, thermal stability, and corrosion resistance. Materials & design, 220, Article ID 110827.
Open this publication in new window or tab >>Combinatorial design of amorphous TaNiSiC thin films with enhanced hardness, thermal stability, and corrosion resistance
Show others...
2022 (English)In: Materials & design, ISSN 0264-1275, E-ISSN 1873-4197, Vol. 220, article id 110827Article in journal (Refereed) Published
Abstract [en]

Amorphous TaNiSiC and TaNiC films (with varying Ta/Ni and Si/C ratios) were deposited using combinatorial magnetron sputtering. The TaNiSiC films remained X-ray amorphous after four hour-long annealings up to 700 °C, while TaNiC alloys with high Ni and C contents crystallized. These differences were attributed to a strong driving force for separation of Ni and C in TaNiC, whereas the addition of Si, due to its solubility in the other elements, reduced the elemental segregation in TaNiSiC. The as-deposited TaNiSiC films exhibited hardnesses of 9–12 GPa. Annealing led to an increase in hardness by 2–4 GPa, due to decreases in average atomic distance, as evidenced by X-ray diffraction measurements. Potentiodynamic polarizations from –0.7 to +1.5 V vs. Ag/AgCl (3 M NaCl) in 10 mM sodium borate showed lower current densities by up to 2 orders of magnitude with increasing Ta content (28–52 at.%). Changes in Si/C content (7–13 at.% Si) had no effect. However, optical microscopy showed that TaNiSiC films with high Si/low C contents (13/10 at.%) suffered much less localized etching compared to TaNiC films. Thus, Si had a significant role in increasing the mechanical strength, corrosion resistance, and thermal stability of the TaNiSiC films.

Place, publisher, year, edition, pages
Elsevier, 2022
Keywords
Metal lic glasses, thermal stability, mechanical properties, corrosion resis- tance
National Category
Materials Chemistry Condensed Matter Physics
Identifiers
urn:nbn:se:uu:diva-468121 (URN)10.1016/j.matdes.2022.110827 (DOI)000826404700006 ()
Funder
Swedish Foundation for Strategic Research, GMT14-0048Swedish Research CouncilSwedish Research Council
Available from: 2022-02-20 Created: 2022-02-20 Last updated: 2022-08-12Bibliographically approved
Osinger, B., Mao, H., Fritze, S., Riekehr, L., Jansson, U. & Lewin, E. (2022). Investigation of the phase formation in magnetron sputtered hard multicomponent (HfNbTiVZr)C coatings. Materials & design, 221, Article ID 111002.
Open this publication in new window or tab >>Investigation of the phase formation in magnetron sputtered hard multicomponent (HfNbTiVZr)C coatings
Show others...
2022 (English)In: Materials & design, ISSN 0264-1275, E-ISSN 1873-4197, Vol. 221, article id 111002Article in journal (Refereed) Published
Abstract [en]

Multicomponent carbides have gained interest especially for ultra-high temperature applications, due to their ceramic hardness, good oxidation resistance and enhanced strength. In this study the phase forma-tion, stability and mechanical properties of (HfNbTiVZr)C multicomponent carbide coatings were inves-tigated. Phase stability was predicted by the CALPHAD (CALculation of PHAse Diagrams) methods. This revealed that the multicomponent solid solution phase is only stable at elevated temperatures, namely above 2400 degrees C. At lower temperatures a phase mixture was predicted, with a particular tendency for V to segregate. Magnetron sputtered thin films deposited at 300 degrees C exhibited a single NaCl-type multicom-ponent carbide phase, which attributes to the kinetic stabilisation of simple structures during thin film growth. Films deposited at 700 degrees C, or exposed to UHV annealing at 1000 degrees C, however, revealed the decom-position of the single-phase multicomponent carbide by partial elemental segregation and formation of additional phases. Thus, confirming the CALPHAD predictions. These results underscore the importance of explicitly considering temperature when discussing the stability of multicomponent carbide materials, as well as the applicability of CALPHAD methods for predicting phase formation and driving forces in these materials. The latter being crucial for designing materials, such as carbides, that are used in appli-cations at elevated temperatures.

Place, publisher, year, edition, pages
ElsevierElsevier BV, 2022
Keywords
High entropy ceramics, Multi -principal element carbide, Multicomponent carbide, Physical vapour deposition (PVD), CALPHAD
National Category
Materials Chemistry
Identifiers
urn:nbn:se:uu:diva-482676 (URN)10.1016/j.matdes.2022.111002 (DOI)000839257000004 ()
Funder
Swedish Research Council, 2018-04834Swedish Research CouncilSwedish Research Council, 2017-00646_9Swedish Foundation for Strategic Research, RIF14-0053
Available from: 2022-09-07 Created: 2022-09-07 Last updated: 2024-01-15Bibliographically approved
Mukhamedov, B., Fritze, S., Ottosson, M., Osinger, B., Lewin, E., Alling, B., . . . Abrikosov, I. (2022). Tetragonal distortion in magnetron sputtered bcc-W films with supersaturated carbon. Materials & design, 214, Article ID 110422.
Open this publication in new window or tab >>Tetragonal distortion in magnetron sputtered bcc-W films with supersaturated carbon
Show others...
2022 (English)In: Materials & design, ISSN 0264-1275, E-ISSN 1873-4197, Vol. 214, article id 110422Article in journal (Refereed) Published
Abstract [en]

Carbon has a low solid solubility in bcc tungsten at equilibrium. However, metastable supersaturated solid solutions can be synthesized with magnetron sputtering. Here, we present a systematic study on the phase stability and mechanical properties of such supersaturated W–C solid solutions. Θ–2θ scans show a split of the 200/020 and the 002 peaks for supersaturated films which is explained by a tetragonal distortion of the bcc structure. This split increases with increasing C content and is maximized at 4 at.% C, where we observe an a/b axis of 3.15–3.16 Å and a c-axis of 3.21–3.22 Å. We performed first-principles calculations of lattice parameters, mixing enthalpies, elastic constants and polycrystalline elastic moduli for cubic and tetragonal W–C solid solutions. Calculations show that tetragonal structure is more stable than the bcc supersaturated solid solution and the calculated lattice parameters and Young’s moduli follow the same trends as the experimental ones as a function of C concentration. The results suggest that supersaturated films with lattice distortion can be used as a design approach to improve the properties of transition metal films with a bcc structure.

Place, publisher, year, edition, pages
ElsevierElsevier BV, 2022
National Category
Materials Chemistry
Identifiers
urn:nbn:se:uu:diva-470304 (URN)10.1016/j.matdes.2022.110422 (DOI)000761243900006 ()
Funder
Swedish Foundation for Strategic Research , 2019-05403Swedish Foundation for Strategic Research , FFL 15-0290Linköpings universitetKnut and Alice Wallenberg Foundation, KAW-2018.0194Swedish Research Council, 2009 00971Swedish Research Council, 2018-04834
Available from: 2022-03-22 Created: 2022-03-22 Last updated: 2024-01-15Bibliographically approved
Zendejas Medina, L., Tavares da Costa, M. V., Paschalidou, E. M., Lindwall, G., Riekehr, L., Korvela, M., . . . Jansson, U. (2021). Enhancing corrosion resistance, hardness, and crack resistance in magnetron sputtered high entropy CoCrFeMnNi coatings by adding carbon. Materials & design, 205, Article ID 109711.
Open this publication in new window or tab >>Enhancing corrosion resistance, hardness, and crack resistance in magnetron sputtered high entropy CoCrFeMnNi coatings by adding carbon
Show others...
2021 (English)In: Materials & design, ISSN 0264-1275, E-ISSN 1873-4197, Vol. 205, article id 109711Article in journal (Refereed) Published
Abstract [en]

This study explores carbon addition as a materials design approach for simultaneously improving the hardness, crack resistance, and corrosion resistance of high entropy thin films. CoCrFeMnNi was selected as a starting point, due to its high concentration of weak carbide formers. The suppression of carbides is crucial to the approach, as carbide formation can decrease both ductility and corrosion resistance. Films with 0, 6, and 11 at.% C were deposited by magnetron co-sputtering, using a graphite target and a sintered compound target. The samples with 0 at.% C crystallized with a mixture of a cubic closed packed (ccp) phase and the intermetallic χ-phase. With 6 and 11 at.% C, the films were amorphous and homogenous down to the nm-scale. The hardness of the films increased from 8 GPa in the carbon-free film to 16 GPa in the film with 11 at.% C. Furthermore, the carbon significantly improved the crack resistance as shown in fragmentation tests, where the crack density was strongly reduced. The changes in mechanical properties were primarily attributed to the shift from crystalline to amorphous. Lastly, the carbon improved the corrosion resistance by a progressive lowering of the corrosion current and the passive current with increasing carbon concentration.

Place, publisher, year, edition, pages
Elsevier, 2021
Keywords
Thin film, Magnetron sputtering, Corrosion, Fragmentation test, Amorphous alloys, Bipolar plate
National Category
Materials Chemistry Inorganic Chemistry
Identifiers
urn:nbn:se:uu:diva-448906 (URN)10.1016/j.matdes.2021.109711 (DOI)000659520300002 ()
Funder
Swedish Research Council, 821-2012-5144Swedish Research Council, 2017-00646_9Swedish Foundation for Strategic Research , RIF14-0053Swedish Research Council, 2018-04834Vinnova, 2016-05156
Available from: 2021-07-13 Created: 2021-07-13 Last updated: 2024-01-15Bibliographically approved
Casillas-Trujillo, L., Osinger, B., Lindblad, R., Karlsson, D., Abrikosov, A. I., Fritze, S., . . . Lewin, E. (2021). Experimental and theoretical evidence of charge transfer in multi-component alloys: how chemical interactions reduce atomic size mismatch. Materials Chemistry Frontiers, 5(15), 5746-5759
Open this publication in new window or tab >>Experimental and theoretical evidence of charge transfer in multi-component alloys: how chemical interactions reduce atomic size mismatch
Show others...
2021 (English)In: Materials Chemistry Frontiers, E-ISSN 2052-1537, Vol. 5, no 15, p. 5746-5759Article in journal (Refereed) Published
Abstract [en]

Ab initio simulations of a multi-component alloy using density functional theory (DFT) were combined with experiments on thin films of the same material using X-ray photoelectron spectroscopy (XPS) to study the connection between the electronic and atomic structures of multi-component alloys. The DFT simulations were performed on an equimolar HfNbTiVZr multi-component alloy. Structure and charge transfer were evaluated using relaxed, non-relaxed, as well as elemental reference structures. The use of a fixed sphere size model allowed quantification of charge transfer, and separation into different contributions. The charge transfer was generally found to follow electronegativity trends and results in a reduced size mismatch between the elements, and thus causes a considerable reduction of the lattice distortions compared to a traditional assumption based on tabulated atomic radii. A calculation of the average deviation from the average radius (i.e. the so-called δ-parameter) based on the atomic Voronoi volumes gave a reduction of δ from ca. 6% (using the volumes in elemental reference phases) to ca. 2% (using the volumes in the relaxed multi-component alloy phase). The reliability of the theoretical results was confirmed by XPS measurements of a Hf22Nb19Ti18V19Zr21 thin film deposited by sputter deposition. The experimentally observed core level binding energy shifts (CLS), as well as peak broadening due to a range of chemical surroundings, for each element showed good agreement with the calculated DFT values. The single solid solution phase of the sample was confirmed by X-ray diffraction (XRD) and transmission electron microscopy (TEM) including energy dispersive spectroscopy (EDS) with nm-resolution. These observations show that the HfNbTiVZr solid solution phase is non-ideal, and that chemical bonding plays an important part in the structure formation, and presumably also in the properties. Our conclusions should be transferable to other multi-component alloy systems, as well as some other multi-component material systems, and open up interesting possibilities for the design of material properties via the electronic structure and controlled charge transfer between selected metallic elements in the materials.

Place, publisher, year, edition, pages
Royal Society of ChemistryRoyal Society of Chemistry (RSC), 2021
National Category
Materials Chemistry Condensed Matter Physics
Identifiers
urn:nbn:se:uu:diva-468314 (URN)10.1039/d1qm00380a (DOI)000664149100001 ()
Funder
Swedish Research Council, 2018-04834Swedish Research Council, 2019-05403Swedish Research Council, 2018-05973Swedish Research Council, 2019-05487Knut and Alice Wallenberg Foundation, KAW-2018.0194Swedish Foundation for Strategic Research , FFL 15-0290Swedish National Infrastructure for Computing (SNIC)
Available from: 2022-02-25 Created: 2022-02-25 Last updated: 2024-01-15Bibliographically approved
Srinath, A., von Fieandt, K., Lindblad, R., Fritze, S., Korvela, M., Pettersson, J., . . . Nyholm, L. (2021). Influence of the nitrogen content on the corrosion resistances of multicomponent AlCrNbYZrN coatings. Corrosion Science, 188, Article ID 109557.
Open this publication in new window or tab >>Influence of the nitrogen content on the corrosion resistances of multicomponent AlCrNbYZrN coatings
Show others...
2021 (English)In: Corrosion Science, ISSN 0010-938X, E-ISSN 1879-0496, Vol. 188, article id 109557Article in journal (Refereed) Published
Abstract [en]

In this study, the relationship between the nitrogen content and the corrosion resistances of non-equimolar multicomponent AlCrNbYZrN films (N = 13-49 at.%) is probed. While there was no linear relationship between nitrogen content and corrosion resistance, the results clearly show that the corrosion resistances of the films were instead determined by their nitrogen-induced porosities i.e. the less porous the sample, the higher the corrosion resistance. The 23, 30 and 37 at.% N samples were denser while the 13 at.% N sample was porous and the 49 at.% N film had an underdense nanocrystalline columnar cross section permitting the ingress of electrolyte.

Keywords
Multicomponent alloy, Multi-principal element nitride, Corrosion, Porosity, X-ray photoelectron spectroscopy
National Category
Corrosion Engineering Inorganic Chemistry Materials Chemistry
Identifiers
urn:nbn:se:uu:diva-448997 (URN)10.1016/j.corsci.2021.109557 (DOI)000663137900001 ()
Funder
Swedish Research Council, C0514401Swedish Foundation for Strategic Research , RIF140053
Note

Jean Pettersson's surname is misspelled to Petersson in the publication

Available from: 2021-09-10 Created: 2021-09-10 Last updated: 2022-02-23Bibliographically approved
Fritze, S., Chen, M., Riekehr, L., Osinger, B., Sortica, M. A., Srinath, A., . . . Jansson, U. (2021). Magnetron sputtering of carbon supersaturated tungsten films-A chemical approach to increase strength. Materials & design, 208, Article ID 109874.
Open this publication in new window or tab >>Magnetron sputtering of carbon supersaturated tungsten films-A chemical approach to increase strength
Show others...
2021 (English)In: Materials & design, ISSN 0264-1275, E-ISSN 1873-4197, Vol. 208, article id 109874Article in journal (Refereed) Published
Abstract [en]

Tungsten (W)-based materials attract significant attention due to their superior mechanical properties. Here, we present a chemical approach based on the addition of carbon (C) for increased strength via the combination of three strengthening mechanisms in W thin films. W:C thin films with C concentrations up to-4 at.% were deposited by magnetron sputtering. All films exhibit a body-centred-cubic structure with strong texture and columnar growth behaviour. X-ray and electron diffraction measurements suggest the formation of supersaturated W:C solid solution phases. The addition of C reduced the average column width from-133 nm for W to-20 nm for the film containing-4 at.% C. The column refinement is explained by a mechanism where C acts as re-nucleation sites. The W film is-13 GPa hard, while the W:C films achieve a peak hardness of-24 GPa. The W:C films are-11 GPa harder than the W film, which is explained by a combination of grain refinement strengthening, solid solution strengthening and increased dislocation density. Additional micropillar compression tests showed that the flow stress increased upon C addition, from-3.8 to-8.3 GPa and no brittle fracture was observed.

Place, publisher, year, edition, pages
ElsevierElsevier BV, 2021
Keywords
Small-scale mechanical characterisation, Tungsten, PVD, Supersaturated solid solution
National Category
Materials Chemistry
Identifiers
urn:nbn:se:uu:diva-453476 (URN)10.1016/j.matdes.2021.109874 (DOI)000684858300005 ()
Funder
Swedish Research Council, 201804834Swedish Foundation for Strategic Research Swedish Research CouncilSwedish Research Council, 82120125144Swedish Research Council, 201700646_9Swedish Foundation for Strategic Research , RIF140053
Available from: 2021-09-23 Created: 2021-09-23 Last updated: 2024-01-15Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-8082-1671

Search in DiVA

Show all publications