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Coradini DSR, Tunes MA, Willenshofer P, Samberger S, Kremmer T, Dumitraschkewitz P, Uggowitzer PJ, Pogatscher S. In situ transmission electron microscopy as a toolbox for the emerging science of nanometallurgy. Lab Chip 2023. [PMID: 37325906 DOI: 10.1039/d3lc00228d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Potential applications of nanomaterials range from electronics to environmental technology, thus a better understanding of their manufacturing and manipulation is of paramount importance. The present study demonstrates a methodology for the use of metallic nanomaterials as reactants to examine nanoalloying in situ within a transmission electron microscope. The method is further utilised as a starting point of a metallurgical toolbox, e.g. to study subsequent alloying of materials by using a nanoscale-sized chemical reactor for nanometallurgy. Cu nanowires and Au nanoparticles are used for alloying with pure Al, which served as the matrix material in the form of electron transparent lamellae. The results showed that both the Au and Cu nanomaterials alloyed when Al was melted in the transmission electron microscope. However, the eutectic reaction was more pronounced in the Al-Cu system, as predicted from the phase diagram. Interestingly, the mixing of the alloying agents occurred independently of the presence of an oxide layer surrounding the nanowires, nanoparticles, or the Al lamellae while performing the experiments. Overall, these results suggest that transmission electron microscope-based in situ melting and alloying is a valuable lab-on-a-chip technique to study the metallurgical processing of nanomaterials for the future development of advanced nanostructured materials.
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Affiliation(s)
| | - Matheus A Tunes
- Materials Science and Technology Division, Los Alamos National Laboratory, USA.
| | | | | | - Thomas Kremmer
- Chair of Non-Ferrous Metallurgy, Montanunversitaet Leoben, Austria.
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2
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Honaramooz MT, Morak R, Pogatscher S, Fritz-Popovski G, Kremmer TM, Meisel TC, Österreicher JA, Arnoldt A, Paris O. Characterization of Zr-Containing Dispersoids in Al-Zn-Mg-Cu Alloys by Small-Angle Scattering. Materials (Basel) 2023; 16:1213. [PMID: 36770221 PMCID: PMC9919802 DOI: 10.3390/ma16031213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 01/13/2023] [Accepted: 01/24/2023] [Indexed: 06/18/2023]
Abstract
The characterization of Zr-containing dispersoids in aluminum alloys is challenging due to their broad size distribution, low volume fraction, and heterogeneous distribution within the grains. In this work, small-angle X-ray scattering (SAXS) and small-angle neutron scattering (SANS) were compared to scanning electron microscopy (SEM) and transmission electron microscopy (TEM) regarding their capability to characterize Zr-containing dispersoids in aluminum alloys. It was demonstrated that both scattering techniques are suitable tools to characterize dispersoids in a multi-phase industrial 7xxx series aluminum alloy. While SAXS is more sensitive than SANS due to the high electron density of Zr-containing dispersoids, SANS has the advantage of being able to probe a much larger sample volume. The combination of both scattering techniques allows for the verification that the contribution from dispersoids can be separated from that of other precipitate phases such as the S-phase or GP-zones. The size distributions obtained from SAXS, SANS and TEM showed good agreement. The SEM-derived size distributions were, however, found to significantly deviate from those of the other techniques, which can be explained by considering the resolution-limited restrictions of the different techniques.
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Affiliation(s)
- Mohammad Taha Honaramooz
- Chair of Physics, Department Physics, Mechanics and Electrical Engineering, Montanuniverstät Leoben, Franz-Josef-Str. 18, 8700 Leoben, Austria
| | - Roland Morak
- R&D Material Science CMI, Center for Material Innovation, AMAG Rolling GmbH, Postfach 32, 5282 Ranshofen, Austria
| | - Stefan Pogatscher
- Chair of Nonferrous Metallurgy, Department Metallurgy, Montanuniverstät Leoben, Franz-Josef-Str. 18, 8700 Leoben, Austria
| | - Gerhard Fritz-Popovski
- Chair of Physics, Department Physics, Mechanics and Electrical Engineering, Montanuniverstät Leoben, Franz-Josef-Str. 18, 8700 Leoben, Austria
| | - Thomas M. Kremmer
- Chair of Nonferrous Metallurgy, Department Metallurgy, Montanuniverstät Leoben, Franz-Josef-Str. 18, 8700 Leoben, Austria
| | - Thomas C. Meisel
- Chair of General and Analytical Chemistry, Department General, Analytical and Physical Chemistry, Montanuniverstät Leoben, Franz-Josef-Str. 18, 8700 Leoben, Austria
| | - Johannes A. Österreicher
- LKR Light Metals Technologies, Austrian Institute of Technology, Lamprechtshausenerstraße 61, 5282 Ranshofen, Austria
| | - Aurel Arnoldt
- LKR Light Metals Technologies, Austrian Institute of Technology, Lamprechtshausenerstraße 61, 5282 Ranshofen, Austria
| | - Oskar Paris
- Chair of Physics, Department Physics, Mechanics and Electrical Engineering, Montanuniverstät Leoben, Franz-Josef-Str. 18, 8700 Leoben, Austria
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3
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Quick CR, Dumitraschkewitz P, Schawe JEK, Pogatscher S. Fast differential scanning calorimetry to mimic additive manufacturing processing: specific heat capacity analysis of aluminium alloys. J Therm Anal Calorim 2022; 148:651-662. [PMID: 36744048 PMCID: PMC9892126 DOI: 10.1007/s10973-022-11824-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 11/19/2022] [Indexed: 06/18/2023]
Abstract
Eutectic AlSi12, commonly used in casting and in additive manufacturing, is investigated with Fast Differential Scanning Calorimetry to determine the impact of different cooling rates from the liquid state upon the apparent specific heat capacity on subsequent heating. A heat flow correction strategy is developed and refined for the reliable and precise measurement of sample heat flow using chip sensors and assessed by the evaluation of results on pure (99.999%) aluminium. That strategy is then applied to the study of the AlSi12 eutectic alloy, and rate-dependent perturbations in the measured apparent specific heat capacity are discussed in terms of Si supersaturation and precipitation. Several cooling rates were implemented from - 100 to - 30,000 K s-1, and subsequent heating ranged from + 1000 to + 30,000 K s-1. After rapid cooling, a drop in AlSi12 apparent specific heat capacity is found on heating above ~ 400 °C; even at rates of + 10,000 K s-1, a result which has high relevance in metal additive manufacturing where similarly fast temperature cycles are involved. The Literature data, temperature modulated DSC and CALPHAD simulations on the heat capacity of AlSi12 are used to provide comparative context to the results from Fast Differential Scanning Calorimetry.
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Affiliation(s)
- Cameron R. Quick
- Chair of Non-Ferrous Metallurgy, Montanuniversitaet Leoben, Leoben, Austria
| | | | - Jürgen E. K. Schawe
- Mettler-Toledo GmbH, Analytical, 8606 Nänikon, Switzerland
- Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, 8093 Zurich, Switzerland
| | - Stefan Pogatscher
- Chair of Non-Ferrous Metallurgy, Montanuniversitaet Leoben, Leoben, Austria
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4
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Tunes MA, Greaves G, Rack PD, Boldman WL, Schön CG, Pogatscher S, Maloy SA, Zhang Y, El-Atwani O. Irradiation stability and induced ferromagnetism in a nanocrystalline CoCrCuFeNi highly-concentrated alloy. Nanoscale 2021; 13:20437-20450. [PMID: 34859248 PMCID: PMC8675024 DOI: 10.1039/d1nr04915a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 09/29/2021] [Indexed: 05/04/2023]
Abstract
In the field of radiation damage of crystalline solids, new highly-concentrated alloys (HCAs) are now considered to be suitable candidate materials for next generation fission/fusion reactors due to recently recorded outstanding radiation tolerance. Despite the preliminarily reported extraordinary properties, the mechanisms of degradation, phase instabilities and decomposition of HCAs are still largely unexplored fields of research. Herein, we investigate the response of a nanocrystalline CoCrCuFeNi HCA to thermal annealing and heavy ion irradiation in the temperature range from 293 to 773 K with the objective to analyze the stability of the nanocrystalline HCA in extreme conditions. The results led to the identification of two regimes of response to irradiation: (i) in which the alloy was observed to be tolerant under extreme irradiation conditions and (ii) in which the alloy is subject to matrix phase instabilities. The formation of FeCo monodomain nanoparticles under these conditions is also reported and a differential phase contrast study in the analytical electron-microscope is carried out to qualitatively probe its magnetic properties.
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Affiliation(s)
- Matheus A Tunes
- Materials Science and Technology Division, Los Alamos National Laboratory, USA.
| | - Graeme Greaves
- School of Computing and Engineering, University of Huddersfield, UK
| | - Philip D Rack
- Joint Staff Center of Nanophase Materials Sciences, Oak Ridge National Laboratory, USA
- Materials Science and Engineering Department, University of Tennessee, USA.
| | - Walker L Boldman
- Materials Science and Engineering Department, University of Tennessee, USA.
| | - Cláudio G Schön
- Department of Metallurgical and Materials Engineering, Escola Politécnica, Universidade de São Paulo, Brazil
| | | | - Stuart A Maloy
- Materials Science and Technology Division, Los Alamos National Laboratory, USA.
| | - Yanwen Zhang
- Materials Science and Engineering Department, University of Tennessee, USA.
- Materials Science and Technology Division, Oak Ridge National Laboratory, USA
| | - Osman El-Atwani
- Materials Science and Technology Division, Los Alamos National Laboratory, USA.
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5
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Papenberg NP, Gneiger S, Uggowitzer PJ, Pogatscher S. Lean Wrought Magnesium Alloys. Materials (Basel) 2021; 14:ma14154282. [PMID: 34361475 PMCID: PMC8348044 DOI: 10.3390/ma14154282] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 07/09/2021] [Accepted: 07/26/2021] [Indexed: 11/23/2022]
Abstract
Lean magnesium alloys are considered attractive candidates for easy and economical hot forming. Such wrought alloys, defined here as materials with a maximum alloying content of one atomic or two weight percent, are known to achieve attractive mechanical properties despite their low alloy content. The good mechanical properties and the considerable hardening potential, combined with the ease of processing, make them attractive for manufacturers and users alike. This results in potential uses in a wide range of applications, from rolled or extruded components to temporary biomedical implants. The characteristic behavior of these alloys and the optimal use of suitable alloying elements are discussed and illustrated exemplarily.
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Affiliation(s)
- Nikolaus P. Papenberg
- LKR Light Metals Technologies Ranshofen, Austrian Institute of Technology, A-5280 Ranshofen, Austria;
- Correspondence:
| | - Stefan Gneiger
- LKR Light Metals Technologies Ranshofen, Austrian Institute of Technology, A-5280 Ranshofen, Austria;
| | - Peter J. Uggowitzer
- Chair of Nonferrous Metallurgy, Montanuniversität Leoben, A-8700 Leoben, Austria; (P.J.U.); (S.P.)
| | - Stefan Pogatscher
- Chair of Nonferrous Metallurgy, Montanuniversität Leoben, A-8700 Leoben, Austria; (P.J.U.); (S.P.)
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6
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Grasserbauer J, Weißensteiner I, Falkinger G, Uggowitzer PJ, Pogatscher S. Influence of Fe and Mn on the Microstructure Formation in 5xxx Alloys-Part II: Evolution of Grain Size and Texture. Materials (Basel) 2021; 14:3312. [PMID: 34203865 PMCID: PMC8232693 DOI: 10.3390/ma14123312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 06/10/2021] [Accepted: 06/11/2021] [Indexed: 11/16/2022]
Abstract
In recent decades, microstructure and texture engineering has become an indispensable factor in meeting the rising demands in mechanical properties and forming behavior of aluminum alloys. Alloying elements, such as Fe and Mn in AlMg(Mn) alloys, affect the number density, size and morphology of both the primary and secondary phases, thus altering the grain size and orientation of the final annealed sheet by Zener pinning and particle stimulated nucleation (PSN). The present study investigates the grain size and texture of four laboratory processed AlMg(Mn) alloys with various Fe and Mn levels (see Part I). Common models for deriving the Zener-limit grain size are discussed in the light of the experimental data. The results underline the significant grain refinement by dispersoids in high Mn alloys and show a good correlation with the Smith-Zener equation, when weighting the volume fraction of the dispersoids with an exponent of 0.33. Moreover, for high Fe alloys a certain reduction in the average grain size is obtained due to pinning effects and PSN of coarse primary phases. The texture analysis focuses on characteristic texture transformations occurring with pinning effects and PSN. However, the discussion of the texture and typical PSN components is only possible in terms of trends, as all alloys exhibit an almost random distribution of orientations.
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Affiliation(s)
- Jakob Grasserbauer
- Christian Doppler Laboratory for Advanced Aluminum Alloys, Chair of Nonferrous Metallurgy, Montanuniversitaet Leoben, Franz-Josef Straße 18, 8700 Leoben, Austria; (I.W.); (S.P.)
| | - Irmgard Weißensteiner
- Christian Doppler Laboratory for Advanced Aluminum Alloys, Chair of Nonferrous Metallurgy, Montanuniversitaet Leoben, Franz-Josef Straße 18, 8700 Leoben, Austria; (I.W.); (S.P.)
| | | | - Peter J. Uggowitzer
- Chair of Nonferrous Metallurgy, Department Metallurgy, Montanuniversitaet Leoben, Franz-Josef Straße 18, 8700 Leoben, Austria;
| | - Stefan Pogatscher
- Christian Doppler Laboratory for Advanced Aluminum Alloys, Chair of Nonferrous Metallurgy, Montanuniversitaet Leoben, Franz-Josef Straße 18, 8700 Leoben, Austria; (I.W.); (S.P.)
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7
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Grasserbauer J, Weißensteiner I, Falkinger G, Kremmer TM, Uggowitzer PJ, Pogatscher S. Influence of Fe and Mn on the Microstructure Formation in 5xxx Alloys-Part I: Evolution of Primary and Secondary Phases. Materials (Basel) 2021; 14:ma14123204. [PMID: 34200776 PMCID: PMC8230420 DOI: 10.3390/ma14123204] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 06/04/2021] [Accepted: 06/07/2021] [Indexed: 11/16/2022]
Abstract
The increasing demands for Al sheets with superior mechanical properties and excellent formability require a profound knowledge of the microstructure and texture evolution in the course of their production. The present study gives a comprehensive overview on the primary- and secondary phase formation in AlMg(Mn) alloys with varying Fe and Mn additions, including variations in processing parameters such as solidification conditions, homogenization temperature, and degree of cold rolling. Higher Fe alloying levels increase the primary phase fraction and favor the needle-shaped morphology of the constituent phases. Increasing Mn additions alter both the shape and composition of the primary phase particles, but also promote the formation of dispersoids as secondary phases. The size, morphology, and composition of primary and secondary phases is further affected by the processing parameters. The average dispersoid size increases significantly with higher homogenization temperature and large primary particles tend to fragment during cold rolling. The microstructures of the final soft annealed states reflect the important effects of the primary and secondary phase particles on their evolution. The results presented in this paper regarding the relevant secondary phases provide the basis for an in-depth discussion of the mechanisms underlying the microstructure formation, such as Zener pinning, particle stimulated nucleation, and texture evolution, which is presented in Part II of this study.
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Affiliation(s)
- Jakob Grasserbauer
- Christian Doppler Laboratory for Advanced Aluminum Alloys, Chair of Nonferrous Metallurgy, Montanuniversitaet Leoben, Franz-Josef Straße 18, 8700 Leoben, Austria; (I.W.); (S.P.)
- Correspondence: ; Tel.: +43-384-2402-5255
| | - Irmgard Weißensteiner
- Christian Doppler Laboratory for Advanced Aluminum Alloys, Chair of Nonferrous Metallurgy, Montanuniversitaet Leoben, Franz-Josef Straße 18, 8700 Leoben, Austria; (I.W.); (S.P.)
| | | | - Thomas M. Kremmer
- Chair of Nonferrous Metallurgy, Department Metallurgy, Montanuniversitaet Leoben, Franz-Josef Straße 18, 8700 Leoben, Austria; (T.M.K.); (P.J.U.)
| | - Peter J. Uggowitzer
- Chair of Nonferrous Metallurgy, Department Metallurgy, Montanuniversitaet Leoben, Franz-Josef Straße 18, 8700 Leoben, Austria; (T.M.K.); (P.J.U.)
| | - Stefan Pogatscher
- Christian Doppler Laboratory for Advanced Aluminum Alloys, Chair of Nonferrous Metallurgy, Montanuniversitaet Leoben, Franz-Josef Straße 18, 8700 Leoben, Austria; (I.W.); (S.P.)
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8
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Tunes MA, Imtyazuddin M, Kainz C, Pogatscher S, Vishnyakov VM. Deviating from the pure MAX phase concept: Radiation-tolerant nanostructured dual-phase Cr 2AlC. Sci Adv 2021; 7:7/13/eabf6771. [PMID: 33762345 PMCID: PMC7990341 DOI: 10.1126/sciadv.abf6771] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 02/03/2021] [Indexed: 05/07/2023]
Abstract
A dual-phase Cr2AlC material was synthesized using magnetron sputtering at a temperature of 648 K. A stoichiometric and nanocrystalline MAX phase matrix was observed along with the presence of spherical-shaped amorphous nano-zones as a secondary phase. The irradiation resistance of the material was assessed using a 300-keV Xe ion beam in situ within a transmission electron microscope up to 40 displacements per atom at 623 K: a condition that extrapolates the harmful environments of future fusion and fission nuclear reactors. At the maximum dose investigated, complete amorphization was not observed. Scanning transmission electron microscopy coupled with energy-dispersive x-ray revealed an association between swelling due to inert gas bubble nucleation and growth and radiation-induced segregation and clustering. Counterintuitively, the findings suggest that preexisting amorphous nano-zones can be beneficial to Cr2AlC MAX phase under extreme environments.
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Affiliation(s)
- M A Tunes
- Chair of Nonferrous Metallurgy, Montanuniversitaet Leoben, Leoben, Austria.
| | - M Imtyazuddin
- Institute for Materials Research, University of Huddersfield, Huddersfield, UK.
| | - C Kainz
- Christian Doppler Laboratory for Advanced Coated Cutting Tools, Department of Materials Science, Montanuniversitaet Leoben, Leoben, Austria
| | - S Pogatscher
- Chair of Nonferrous Metallurgy, Montanuniversitaet Leoben, Leoben, Austria
| | - V M Vishnyakov
- Institute for Materials Research, University of Huddersfield, Huddersfield, UK
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9
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Tunes MA, Stemper L, Greaves G, Uggowitzer PJ, Pogatscher S. Prototypic Lightweight Alloy Design for Stellar-Radiation Environments. Adv Sci (Weinh) 2020; 7:2002397. [PMID: 33240778 PMCID: PMC7675061 DOI: 10.1002/advs.202002397] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 08/17/2020] [Indexed: 06/11/2023]
Abstract
The existing literature data shows that conventional aluminium alloys may not be suitable for use in stellar-radiation environments as their hardening phases are prone to dissolve upon exposure to energetic irradiation, resulting in alloy softening which may reduce the lifetime of such materials impairing future human-based space missions. The innovative methodology of crossover alloying is herein used to synthesize an aluminium alloy with a radiation resistant hardening phase. This alloy-a crossover of 5xxx and 7xxx series Al-alloys-is subjected to extreme heavy ion irradiations in situ within a TEM up to a dose of 1 dpa and major experimental observations are made: the Mg32(Zn,Al)49 hardening precipitates (denoted as T-phase) for this alloy system surprisingly survive the extreme irradiation conditions, no cavities are found to nucleate and displacement damage is observed to develop in the form of black-spots. This discovery indicates that a high phase fraction of hardening precipitates is a crucial parameter for achieving superior radiation tolerance. Based on such observations, this current work sets new guidelines for the design of metallic alloys for space exploration.
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Affiliation(s)
- Matheus A. Tunes
- Chair of Nonferrous MetallurgyMontanuniversitaet LeobenLeobenA‐8700Austria
| | - Lukas Stemper
- Christian Doppler Laboratory for Advanced Aluminium AlloysChair of Nonferrous MetallurgyMontanuniversitaet LeobenLeobenA‐8700Austria
| | - Graeme Greaves
- School of Computing and EngineeringUniversity of HuddersfieldHuddersfieldHD1 3DHUnited Kingdom
| | - Peter J. Uggowitzer
- Chair of Nonferrous MetallurgyMontanuniversitaet LeobenLeobenA‐8700Austria
- Laboratory of Metal Physics and TechnologyDepartment of MaterialsETH ZürichZürich8093Switzerland
| | - Stefan Pogatscher
- Chair of Nonferrous MetallurgyMontanuniversitaet LeobenLeobenA‐8700Austria
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10
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Kremmer TM, Dumitraschkewitz P, Pöschmann D, Ebner T, Uggowitzer PJ, Kolb GKH, Pogatscher S. Microstructural Change during the Interrupted Quenching of the AlZnMg(Cu) Alloy AA7050. Materials (Basel) 2020; 13:ma13112554. [PMID: 32512699 PMCID: PMC7321441 DOI: 10.3390/ma13112554] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 05/27/2020] [Accepted: 05/29/2020] [Indexed: 11/23/2022]
Abstract
This study reports on the effect of interrupted quenching on the microstructure and mechanical properties of plates made of the AlZnMg(Cu) alloy AA7050. Rapid cooling from the solution heat treatment temperature is interrupted at temperatures between 100 and 200 °C and continued with a very slow further cooling to room temperature. The final material’s condition is achieved without or with subsequent artificial ageing. The results show that an improvement in the strength–toughness trade-off can be obtained by using this method. Interrupted quenching at 125 °C with peak artificial ageing leads to a yield strength increase of 27 MPa (538 MPa to 565 MPa) compared to the reference material at the same fracture toughness level. A further special case is the complete omission of an artificial ageing treatment with interrupted quenching at 200 °C. This heat treatment exhibits an 20% increase in fracture toughness (35 to 42 MPa m−1/2) while retaining a sufficient yield strength of 512 MPa for industrial applications. A detailed characterization of the relevant microstructural parameters like present phases, phase distribution and precipitate-free zones is performed using transmission electron microscopy and atom probe tomography.
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Affiliation(s)
- Thomas M. Kremmer
- Chair of Nonferrous Metallurgy, Montanuniversitaet Leoben, 8700 Leoben, Austria; (P.D.); (P.J.U.)
- Correspondence: (T.M.K.); (S.P.)
| | - Phillip Dumitraschkewitz
- Chair of Nonferrous Metallurgy, Montanuniversitaet Leoben, 8700 Leoben, Austria; (P.D.); (P.J.U.)
| | - Daniel Pöschmann
- AMAG rolling GmbH, Postfach 32, 5282 Ranshofen, Austria; (D.P.); (T.E.)
| | - Thomas Ebner
- AMAG rolling GmbH, Postfach 32, 5282 Ranshofen, Austria; (D.P.); (T.E.)
| | - Peter J. Uggowitzer
- Chair of Nonferrous Metallurgy, Montanuniversitaet Leoben, 8700 Leoben, Austria; (P.D.); (P.J.U.)
| | - Gernot K. H. Kolb
- Voestalpine Wire Rod Austria GmbH, Drahtstraße 1, 8792 St. Peter/Freienstein, Austria;
| | - Stefan Pogatscher
- Chair of Nonferrous Metallurgy, Montanuniversitaet Leoben, 8700 Leoben, Austria; (P.D.); (P.J.U.)
- Correspondence: (T.M.K.); (S.P.)
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11
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Papenberg NP, Gneiger S, Weißensteiner I, Uggowitzer PJ, Pogatscher S. Mg-Alloys for Forging Applications-A Review. Materials (Basel) 2020; 13:ma13040985. [PMID: 32098352 PMCID: PMC7079650 DOI: 10.3390/ma13040985] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 01/31/2020] [Accepted: 02/02/2020] [Indexed: 12/13/2022]
Abstract
Interest in magnesium alloys and their applications has risen in recent years. This trend is mainly evident in casting applications, but wrought alloys are also increasingly coming into focus. Among the most common forming processes, forging is a promising candidate for the industrial production of magnesium wrought products. This review is intended to give a general introduction into the forging of magnesium alloys and to help in the practical realization of forged products. The basics of magnesium forging practice are described and possible problems as well as material properties are discussed. Several alloy systems containing aluminum, zinc or rare earth elements as well as biodegradable alloys are evaluated. Overall, the focus of the review is on the process control and processing parameters, from stock material to finished parts. A discussion of the mechanical properties is included. These data have been comprehensively reviewed and are listed for a variety of magnesium forging alloys.
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Affiliation(s)
- Nikolaus P. Papenberg
- LKR Light Metals Technologies Ranshofen, Austrian Institute of Technology, A-5282 Ranshofen, Austria;
- Correspondence:
| | - Stefan Gneiger
- LKR Light Metals Technologies Ranshofen, Austrian Institute of Technology, A-5282 Ranshofen, Austria;
| | - Irmgard Weißensteiner
- Christian Doppler Laboratory for Advanced Aluminum Alloys, Chair of Nonferrous Metallurgy, Montanuniversität Leoben, A-8700 Leoben, Austria;
| | - Peter J. Uggowitzer
- Chair of Nonferrous Metallurgy, Montanuniversität Leoben, A-8700 Leoben, Austria; (P.J.U.); (S.P.)
- Department of Materials, Laboratory of Metal Physics and Technology, ETH Zürich, 8093 Zürich, Switzerland
| | - Stefan Pogatscher
- Chair of Nonferrous Metallurgy, Montanuniversität Leoben, A-8700 Leoben, Austria; (P.J.U.); (S.P.)
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12
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Horky J, Ghaffar A, Werbach K, Mingler B, Pogatscher S, Schäublin R, Setman D, Uggowitzer PJ, Löffler JF, Zehetbauer MJ. Exceptional Strengthening of Biodegradable Mg-Zn-Ca Alloys through High Pressure Torsion and Subsequent Heat Treatment. Materials (Basel) 2019; 12:ma12152460. [PMID: 31382378 PMCID: PMC6696220 DOI: 10.3390/ma12152460] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 07/25/2019] [Accepted: 07/30/2019] [Indexed: 12/16/2022]
Abstract
In this study, two biodegradable Mg-Zn-Ca alloys with alloy content of less than 1 wt % were strengthened via high pressure torsion (HPT). A subsequent heat treatment at temperatures of around 0.45 Tm led to an additional, sometimes even larger increase in both hardness and tensile strength. A hardness of more than 110 HV and tensile strength of more than 300 MPa were achieved in Mg-0.2Zn-0.5Ca by this procedure. Microstructural analyses were conducted by scanning and transmission electron microscopy (SEM and TEM, respectively) and atom probe tomography (APT) to reveal the origin of this strength increase. They indicated a grain size in the sub-micron range, Ca-rich precipitates, and segregation of the alloying elements at the grain boundaries after HPT-processing. While the grain size and segregation remained mostly unchanged during the heat treatment, the size and density of the precipitates increased slightly. However, estimates with an Orowan-type equation showed that precipitation hardening cannot account for the strength increase observed. Instead, the high concentration of vacancies after HPT-processing is thought to lead to the formation of vacancy agglomerates and dislocation loops in the basal plane, where they represent particularly strong obstacles to dislocation movement, thus, accounting for the considerable strength increase observed. This idea is substantiated by theoretical considerations and quenching experiments, which also show an increase in hardness when the same heat treatment is applied.
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Affiliation(s)
- Jelena Horky
- Physics of Nanostructured Materials, Faculty of Physics, University of Vienna, 1090 Vienna, Austria.
- Center for Health & Bioresources, Biomedical Systems, AIT Austrian Institute of Technology GmbH, 2700 Wiener Neustadt, Austria.
| | - Abdul Ghaffar
- Physics of Nanostructured Materials, Faculty of Physics, University of Vienna, 1090 Vienna, Austria
- Department of Physics, GC University, 54000 Lahore, Pakistan
| | - Katharina Werbach
- Physics of Nanostructured Materials, Faculty of Physics, University of Vienna, 1090 Vienna, Austria
| | - Bernhard Mingler
- Center for Health & Bioresources, Biomedical Systems, AIT Austrian Institute of Technology GmbH, 2700 Wiener Neustadt, Austria
| | - Stefan Pogatscher
- Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, 8093 Zurich, Switzerland
- Institute of Nonferrous Metallurgy, Montanuniversität Leoben, 8700 Leoben, Austria
| | - Robin Schäublin
- Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, 8093 Zurich, Switzerland
| | - Daria Setman
- Physics of Nanostructured Materials, Faculty of Physics, University of Vienna, 1090 Vienna, Austria
| | - Peter J Uggowitzer
- Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, 8093 Zurich, Switzerland
| | - Jörg F Löffler
- Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, 8093 Zurich, Switzerland
| | - Michael J Zehetbauer
- Physics of Nanostructured Materials, Faculty of Physics, University of Vienna, 1090 Vienna, Austria
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Pogatscher S, Leutenegger D, Schawe JEK, Maris P, Schäublin R, Uggowitzer PJ, Löffler JF. Monotropic polymorphism in a glass-forming metallic alloy. J Phys Condens Matter 2018; 30:234002. [PMID: 29697058 DOI: 10.1088/1361-648x/aac054] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
This study investigates the crystallization and phase transition behavior of the amorphous metallic alloy Au70Cu5.5Ag7.5Si17. This alloy has been recently shown to exhibit a transition of a metastable to a more stable crystalline state, occurring via metastable melting under strong non-equilibrium conditions. Such behavior had so far not been observed in other metallic alloys. In this investigation fast differential scanning calorimetry (FDSC) is used to explore crystallization and the solid-liquid-solid transition upon linear heating and during isothermal annealing, as a function of the conditions under which the metastable phase is formed. It is shown that the occurrence of the solid-liquid-solid transformation in FDSC depends on the initial conditions; this is explained by a history-dependent nucleation of the stable crystalline phase. The microstructure was investigated by scanning and transmission electron microscopy and x-ray diffraction. Chemical mapping was performed by energy dispersive x-ray spectrometry. The relationship between the microstructure and the phase transitions observed in FSDC is discussed with respect to the possible kinetic paths of the solid-liquid-solid transition, which is a typical phenomenon in monotropic polymorphism.
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Affiliation(s)
- S Pogatscher
- Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, 8093 Zurich, Switzerland. Institute of Nonferrous Metallurgy, Montanuniversitaet Leoben, 8700 Leoben, Austria
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Pogatscher S, Leutenegger D, Schawe JEK, Uggowitzer PJ, Löffler JF. Solid-solid phase transitions via melting in metals. Nat Commun 2016; 7:11113. [PMID: 27103085 PMCID: PMC4844691 DOI: 10.1038/ncomms11113] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 02/22/2016] [Indexed: 11/29/2022] Open
Abstract
Observing solid–solid phase transitions in-situ with sufficient temporal and spatial resolution is a great challenge, and is often only possible via computer simulations or in model systems. Recently, a study of polymeric colloidal particles, where the particles mimic atoms, revealed an intermediate liquid state in the transition from one solid to another. While not yet observed there, this finding suggests that such phenomena may also occur in metals and alloys. Here we present experimental evidence for a solid–solid transition via the formation of a metastable liquid in a ‘real' atomic system. We observe this transition in a bulk glass-forming metallic system in-situ using fast differential scanning calorimetry. We investigate the corresponding transformation kinetics and discuss the underlying thermodynamics. The mechanism is likely to be a feature of many metallic glasses and metals in general, and may provide further insight into phase transition theory. Solid–solid phase transition via an intermediate liquid state has been identified in colloidal systems, but the universality of the phenomenon at atomic scales has not yet been proved. Pogatscher et al. observe a similar transition in a metallic glass system using fast differential scanning calorimetry.
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Affiliation(s)
- S Pogatscher
- Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, Zurich 8093, Switzerland.,Institute of Nonferrous Metallurgy, Department of Metallurgy, Montanuniversität Leoben, Leoben 8700, Austria
| | - D Leutenegger
- Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, Zurich 8093, Switzerland
| | - J E K Schawe
- Mettler-Toledo GmbH, Analytical, Schwerzenbach 8603, Switzerland
| | - P J Uggowitzer
- Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, Zurich 8093, Switzerland
| | - J F Löffler
- Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, Zurich 8093, Switzerland
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Hofstetter J, Martinelli E, Pogatscher S, Schmutz P, Povoden-Karadeniz E, Weinberg AM, Uggowitzer PJ, Löffler JF. Influence of trace impurities on the in vitro and in vivo degradation of biodegradable Mg-5Zn-0.3Ca alloys. Acta Biomater 2015; 23:347-353. [PMID: 25983315 DOI: 10.1016/j.actbio.2015.05.004] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2015] [Revised: 05/05/2015] [Accepted: 05/09/2015] [Indexed: 11/29/2022]
Abstract
The hydrogen evolution method and animal experiments were deployed to investigate the effect of trace impurity elements on the degradation behavior of high-strength Mg alloys of type ZX50 (Mg-5Zn-0.3Ca). It is shown that trace impurity elements increase the degradation rate, predominantly in the initial period of the tests, and also increase the material's susceptibility to localized corrosion attack. These effects are explained on the basis of the corrosion potential of the intermetallic phases present in the alloys. The Zn-rich phases present in ZX50 are nobler than the Mg matrix, and thus act as cathodic sites. The impurity elements Fe and Mn in the alloy of conventional purity are incorporated in these Zn-rich intermetallic phases and therefore increase their cathodic efficiency. A design rule for circumventing the formation of noble intermetallic particles and thus avoiding galvanically accelerated dissolution of the Mg matrix is proposed.
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Affiliation(s)
- J Hofstetter
- Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, 8093 Zurich, Switzerland
| | - E Martinelli
- Department of Orthopaedics and Orthopaedic Surgery, Medical University Graz, 8036 Graz, Austria
| | - S Pogatscher
- Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, 8093 Zurich, Switzerland
| | - P Schmutz
- Laboratory for Joining Technologies and Corrosion, EMPA, Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland
| | - E Povoden-Karadeniz
- Christian Doppler Laboratory for Early Stages of Precipitation, Vienna University of Technology, 1040 Vienna, Austria
| | - A M Weinberg
- Department of Orthopaedics and Orthopaedic Surgery, Medical University Graz, 8036 Graz, Austria
| | - P J Uggowitzer
- Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, 8093 Zurich, Switzerland
| | - J F Löffler
- Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, 8093 Zurich, Switzerland.
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Prillhofer R, Rank G, Berneder J, Antrekowitsch H, Uggowitzer PJ, Pogatscher S. Property Criteria for Automotive Al-Mg-Si Sheet Alloys. Materials (Basel) 2014; 7:5047-5068. [PMID: 28788119 PMCID: PMC5455832 DOI: 10.3390/ma7075047] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Revised: 06/13/2014] [Accepted: 06/24/2014] [Indexed: 11/16/2022]
Abstract
In this study, property criteria for automotive Al-Mg-Si sheet alloys are outlined and investigated in the context of commercial alloys AA6016, AA6005A, AA6063 and AA6013. The parameters crucial to predicting forming behavior were determined by tensile tests, bending tests, cross-die tests, hole-expansion tests and forming limit curve analysis in the pre-aged temper after various storage periods following sheet production. Roping tests were performed to evaluate surface quality, for the deployment of these alloys as an outer panel material. Strength in service was also tested after a simulated paint bake cycle of 20 min at 185 °C, and the corrosion behavior was analyzed. The study showed that forming behavior is strongly dependent on the type of alloy and that it is influenced by the storage period after sheet production. Alloy AA6016 achieves the highest surface quality, and pre-ageing of alloy AA6013 facilitates superior strength in service. Corrosion behavior is good in AA6005A, AA6063 and AA6016, and only AA6013 shows a strong susceptibility to intergranular corrosion. The results are discussed below with respect to the chemical composition, microstructure and texture of the Al-Mg-Si alloys studied, and decision-making criteria for appropriate automotive sheet alloys for specific applications are presented.
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Affiliation(s)
- Ramona Prillhofer
- AMAG Rolling GmbH, Lamprechtshausnerstraße 61, 5282 Ranshofen, Austria.
| | - Gunther Rank
- AMAG Rolling GmbH, Lamprechtshausnerstraße 61, 5282 Ranshofen, Austria.
| | - Josef Berneder
- AMAG Rolling GmbH, Lamprechtshausnerstraße 61, 5282 Ranshofen, Austria.
| | - Helmut Antrekowitsch
- Institute of Nonferrous Metallurgy, Montanuniversität Leoben, Franz-Josef-Straße 18, 8700 Leoben, Austria.
| | - Peter J Uggowitzer
- Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, Vladimir-Prelog-Weg 4, 8093 Zürich, Switzerland.
| | - Stefan Pogatscher
- Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, Vladimir-Prelog-Weg 4, 8093 Zürich, Switzerland.
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Pogatscher S, Antrekowitsch H, Werinos M, Moszner F, Gerstl SSA, Francis MF, Curtin WA, Löffler JF, Uggowitzer PJ. Diffusion on demand to control precipitation aging: application to Al-Mg-Si alloys. Phys Rev Lett 2014; 112:225701. [PMID: 24949778 DOI: 10.1103/physrevlett.112.225701] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Indexed: 06/03/2023]
Abstract
We demonstrate experimentally that a part-per-million addition of Sn solutes in Al-Mg-Si alloys can inhibit natural aging and enhance artificial aging. The mechanism controlling the aging is argued to be vacancy diffusion, with solutes trapping vacancies at low temperature and releasing them at elevated temperature, which is supported by a thermodynamic model and first-principles computations of Sn-vacancy binding. This "diffusion on demand" solves the long-standing problem of detrimental natural aging in Al-Mg-Si alloys, which is of great scientific and industrial importance. Moreover, the mechanism of controlled buffering and release of excess vacancies is generally applicable to modulate diffusion in other metallic systems.
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Affiliation(s)
- S Pogatscher
- Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, 8093 Zurich, Switzerland and Institute of Nonferrous Metallurgy, Montanuniversitaet Leoben, 8700 Leoben, Austria
| | - H Antrekowitsch
- Institute of Nonferrous Metallurgy, Montanuniversitaet Leoben, 8700 Leoben, Austria
| | - M Werinos
- Institute of Nonferrous Metallurgy, Montanuniversitaet Leoben, 8700 Leoben, Austria
| | - F Moszner
- Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, 8093 Zurich, Switzerland
| | - S S A Gerstl
- Scientific Center for Optical and Electron Microscopy ScopeM, ETH Zurich, 8093 Zurich, Switzerland
| | - M F Francis
- Institute of Mechanical Engineering, EPFL, 1015 Lausanne, Switzerland
| | - W A Curtin
- Institute of Mechanical Engineering, EPFL, 1015 Lausanne, Switzerland
| | - J F Löffler
- Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, 8093 Zurich, Switzerland
| | - P J Uggowitzer
- Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, 8093 Zurich, Switzerland
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