Dr. rer.nat. Rachid Touzani
Werkstofftechnik
Completed projects
Creep behavior of advanced directionally solidified multi-phase Mo-alloys with and without coating (HTMA-DS Mo)
Duration: 01.03.2020 bis 31.01.2024
Mo-Hf-B and Mo-Zr-B alloys as a new class of refractory alloys are potential candidates in stationary and mobile turbine applications. Due to the high melting points of the constituents high-temperature strength and creep strength are expected up to 1,400 °C. Those high service temperatures, in turn, may result in higher turbine efficiencies and may reduce primary energy consumption.
As a manufacturing route, directional solidification via zone melting as a new processing approach for Mo-Hf-B and Mo-Zr-B results in low oxygen (< 50 ppm) impurities, which is essential to avoid embrittlement of these alloys; moreover the materials possess an anisotropic lamellae-reinforced microstructure.
Density functional theory calculations on metals and intermetallics
Duration: 01.10.2019 bis 30.09.2022
With the aid of density functional theory it is possible to adress many questions regarding metals and intermetallics likewise. Not only it is possible to predict the crystal structure of a solid, but also the ability to investigate and explain site preferences within intermetallics like borides and silicides comes in handy. It is also very important to determine the stability of metals and intermetallics and, in doing so, the electronic and phononic properties is investigated. The phase stability of matrix, side phases and precipitations depends on the temperature and the pressure and therefore one uses first principles calculations to investigate the thermodynamic properties of these metals and intermetallic phases at least qualitatively. The elastic properties of the metals and intermetallics can also be predicted to a very good precision.
Density functional theory is therefore the ideal ansatz to investigate metals and intermetallics as it is accurate and fast.
FlexiDS: Aufklärung der Phasen- und Mikrostrukturbildung während der gerichteten Erstarrung neuer metallischer und intermetallischer Materialien durch in-situ Beobachtung des Erstarrungsvorganges mit Photonenbeugung
Duration: 01.08.2016 bis 31.07.2019
Im Projekt FlexiDS soll in Kooperation mit dem Karlsruher Institut für Technologie (KIT) der Prozess der gerichteten Erstarrung in verschiedenen Hochtemperaturmaterialien mit in-situ Röntgenbeugung untersucht werden. In diesem Rahmen soll eine innovative in-situ Probenumgebung für gerichtete Erstarrung an der HEMS-Beamline (High Energy Material Science) des DESY (Deutschen Elektronen Synchrotron, Hamburg) entwickelt und aufgebaut werden. Diese wird den beteiligten Partnern völlig neue Forschungs- und Charakterisierungsmöglichkeiten durch direkte Beobachtung des gerichteten Erstarrungsprozesses bieten. Das Helmholtz-Zentrum-Geesthacht (HZG), das diese Beamline betreut, wird die Konzeption, den Bau und den Betrieb der Probenumgebung unterstützen.
2024
Peer-reviewed journal article
Effect of oxygen in Mo-TM (TM = Ti, Zr, Hf) solid solutions as studied with density functional theory calculations
Touzani, Rachid; Nizinkovskyi, Rostyslav; Krüger, Manja
In: Crystals - Basel : MDPI, Bd. 14 (2024), Heft 3, Artikel 213, insges. 13 S.
2022
Peer-reviewed journal article
V 8SiB 4 - a new ternary phase in the V-Si-B system
Yang, W. G.; Touzani, Rachid Stefan; Hasemann, Georg; Yazlak, M.; Ziegner, M.; Gorr, B.; Schwaiger, R.; Krüger, Manja
In: Intermetallics - Amsterdam [u.a.] : Elsevier Science, Bd. 151 (2022), Artikel 107691, insges. 12 S.
Microstructure formation of cast and directionally solidified Mo-Ti-B alloys
Petrusha, Vadym; Hasemann, Georg; Touzani, Rachid Stefan; Bolbut, Volodymyr; Bogomol, Iurii; Krüger, Manja
In: Metals - Basel : MDPI, Bd. 12 (2022), Heft 6, Artikel 916, insges. 13 S.
SrAl 5Pt 3 and Sr 2Al 6Pt 9 - two new strontium aluminum platinides
Engel, Stefan; Bönnighausen, Judith; Stegemann, Frank; Touzani, Rachid S.; Janka, Oliver
In: Zeitschrift für Naturforschung / B - Berlin : De Gruyter . - 2022 [Online first]
2021
Abstract
First principles density functional theory prediction of the crystal structure and the elastic properties of Mo2ZrB2 and Mo2HfB2
Touzani, Rachid Stefan; Krüger, Manja
In: Intermetallics 2021 - International Conference, 04-08 October 2021 : Educational Center Kloster Banz, Germany : programme and abstracts , 2021 - Jena, Germany : Conventus Congressmanagement & Marketing GmbH ; Krüger, Manja, S. 94-95, Artikel O-MO-02 [Intermetallics 2021, International Conference, 4th till 8th October 2021 : Educational Center Kloster Banz, Germany]
Peer-reviewed journal article
Synthesis, crystal and electronic structure of CaNi 2Al 8
Gießelmann, Elias; Touzani, Rachid S.; Morgenstern, Bernd; Janka, Oliver
In: Zeitschrift für Naturforschung / B - Berlin : De Gruyter . - 2021 [Online first]
2020
Peer-reviewed journal article
Influence of Nb, Ti and Mo on microstructure and mechanical properties of vanadium solid solutions
Müller, Christopher; Touzani, Rachid S.; Betke, Ulf; Krüger, Manja
In: IOP conference series / Institute of Physics - London [u.a.] : Institute of Physics - Vol. 882 (2020), 012012, insgesamt 10 Seiten [ Symposium: Symposium on Materials and Joining Technology, Magdeburg, Germany, 7-8 September 2020]
First principles density functional theory prediction of the crystal structure and the elastic properties of Mo 2ZrB 2 and Mo 2HfB 2
Touzani, Rachid Stefan; Krüger, Manja
In: Crystals - Basel : MDPI - Volume 10 (2020), issue 10, article 865, 14 Seiten
First principles density functional theory calculations on the elastic properties of Mo-Si based solid solutions
Touzani, Rachid; Krüger, Manja
In: IOP conference series / Institute of Physics - London [u.a.] : Institute of Physics - Vol. 882 (2020), Paper 012024, insgesamt 10 Seiten [Symposium: Symposium on Materials and Joining Technology, Magdeburg, Germany, 7-8 September 2020]
2019
Peer-reviewed journal article
Site preference of V and its influence on the elastic properties in the boride series VxMo5-xSiB2 as studied by first principles density functional theory
Touzani, Rachid Stefan; Becker, Julia; Krüger, Manja
In: Journal of alloys and compounds - Lausanne : Elsevier . - 2019 [Online first]
Unusually strong heteroatomic bonding in the complex polyanion of intermetallic Ba 6Pt 22Al 53
Stegemann, Frank; Touzani, Rachid Stefan; Janka, Oliver
In: Dalton transactions - London : Soc., Bd. 48 (2019), Heft 37, S. 14103-14114
2018
Peer-reviewed journal article
Cr3 Triangles induced competing magnetic interactions in the new metal boride TiCrIr2B2: An NMR and DFT study
Koumoulis, D.; Kupers, M.; Touzani, R.; Zhang, Y.; Fokwa, B.P.T.; Bouchard, L.-S.
In: Materials Research Bulletin, 2018, S. 91-96, ISSN 00255408, 10.1016/j.materresbull.2017.12.011
2016
Peer-reviewed journal article
Sr 2 Pd 4 Al 5 : Synthesis, Crystal and Electronic Structures, and Chemical Bonding of a Polar Intermetallic Compound
Stegemann, Frank; Benndorf, Christopher; Touzani, Rachid St.; Fokwa, Boniface P. T.; Janka, Oliver
In: European Journal of Inorganic Chemistry, 2016, S. 1108-1114, ISSN 14341948, 10.1002/ejic.201501455
EuAu 3 Al 2 : Crystal and Electronic Structures and Spectroscopic, Magnetic, and Magnetocaloric Properties
Schmiegel, Jan-Patrick; Block, Theresa; Gerke, Birgit; Fickenscher, Thomas; Touzani, Rachid St.; Fokwa, Boniface P. T.; Janka, Oliver
In: Inorganic Chemistry, 2016, S. 9057-9064, ISSN 0020-1669, 10.1021/acs.inorgchem.6b01530
Experimental and theoretical investigations of the polar intermetallics SrPt 3 Al 2 and Sr 2 Pd 2 Al
Stegemann, Frank; Benndorf, Christopher; Touzani, Rachid St.; Fokwa, Boniface P.T.; Janka, Oliver
In: Journal of Solid State Chemistry, 2016, S. 143-150, ISSN 00224596, 10.1016/j.jssc.2016.07.019
New ternary tantalum borides containing boron dumbbells: Experimental and theoretical studies of Ta2OsB2 and TaRuB
Mbarki, Mohammed; Touzani, Rachid St.; Rehorn, Christian W.G.; Gladisch, Fabian C.; Fokwa, Boniface P.T.
In: Journal of Solid State Chemistry, 2016, S. 28-33, ISSN 00224596, 10.1016/j.jssc.2016.01.012
2015
Peer-reviewed journal article
Influence of chemical bonding and magnetism on elastic properties of the A2MB2 borides (A=Nb, Ta; M=Fe, Ru, Os) from first-principles calculations
Touzani, Rachid St.; Rehorn, Christian W.G.; Fokwa, Boniface P.T.
In: Computational Materials Science, 2015, S. 52-59, ISSN 09270256, 10.1016/j.commatsci.2015.03.036
Ba 3 Pt 4 Al 4 —Structure, Properties, and Theoretical and NMR Spectroscopic Investigations of a Complex Platinide Featuring Heterocubane [Pt 4 Al 4 ] Units
Stegemann, Frank; Benndorf, Christopher; Bartsch, Timo; Touzani, Rachid St.; Bartsch, Manfred; Zacharias, Helmut; Fokwa, Boniface P. T.; Eckert, Hellmut; Janka, Oliver
In: Inorganic Chemistry, 2015, S. 10785-10793, ISSN 0020-1669, 10.1021/acs.inorgchem.5b01842
Electronic Pseudogap-Driven Formation of New Double-Perovskite-like Borides within the Sc 2 Ir 6– x T x B (T = Pd, Ni; x = 0–6) Series
Hermus, Martin; Scheifers, Jan P.; Touzani, Rachid; Fokwa, Boniface P. T.
In: Inorganic Chemistry, 2015, S. 4056-4063, ISSN 0020-1669, 10.1021/acs.inorgchem.5b00292
2014
Peer-reviewed journal article
Electronic, structural and magnetic studies of niobium borides of group 8 transition metals, Nb2MB2 (M=Fe, Ru, Os) from first principles calculations
Touzani, Rachid St.; Fokwa, Boniface P.T.
In: Journal of Solid State Chemistry, 2014, S. 227-234, ISSN 00224596, 10.1016/j.jssc.2013.10.013
Experimental and Theoretical Investigations of the Ternary Boride NbRuB with a Layerlike Structure Type
Mbarki, Mohammed; Touzani, Rachid St.; Fokwa, Boniface P. T.
In: European Journal of Inorganic Chemistry, 2014, S. 1381-1388, ISSN 14341948, 10.1002/ejic.201301488
Synthesis and Theoretical Investigations of the Solid Solution CeRu 1– x Ni x Al ( x = 0.1–0.95) Showing Cerium Valence Fluctuations
Niehaus, Oliver; Rodewald, Ute Ch.; Abdala, Paula M.; Touzani, Rachid St.; Fokwa, Boniface P. T.; Janka, Oliver
In: Inorganic Chemistry, 2014, S. 2471-2480, ISSN 0020-1669, 10.1021/ic402414f
2013
Peer-reviewed journal article
Nb2OsB2, with a new twofold superstructure of the U3Si2 type: Synthesis, crystal chemistry and chemical bonding
Mbarki, Mohammed; Touzani, Rachid St.; Fokwa, Boniface P.T.
In: Journal of Solid State Chemistry, 2013, S. 304-309, ISSN 00224596, 10.1016/j.jssc.2013.04.018
Otto-von-Guericke-Universität Magdeburg
Institut für Werkstoff- und Fügetechnik (IWF)
Lehrstuhl Metallische Werkstoffe und Lehrstuhl für Hochtemperaturwerkstoffe
Große Steinernetischstraße 6
D-39104 Magdeburg
Telefon: 0391-67-54525
Telefax: 0391-67-44569
Email:
URL: http://www.iwf.ovgu.de/
Lebenslauf
August 1986 geboren in Dortmund
1997-2006 Gesamtschule Gartenstadt Dortmund, Abschluss: Abitur
10/2007–08/2010 Bachelorstudium im Fach Chemie an der RWTH Aachen University
10/2010–10/2012 Masterstudium im Fach Chemie an der RWTH Aachen University
04/2012–10/2012 Studentische Hilfskraft am Institut für Anorganische Chemie der RWTH Aachen University
11/2012–12/2016 Wissenschaftlicher Mitarbeiter am Institut für Anorganische Chemie der RWTH Aachen University
08-09/2014 Forschungsaufenthalt an der Iowa State University, Department of Chemistry, Ames, Iowa, USA: Quantumchemical investigations on NaAu2 and BaGa2
01.04.2016 Promotion im Fach Chemie an der RWTH Aachen University
Dissertation bei Privat-Dozent Dr. Boniface P. T. Fokwa:
Quantenchemische Untersuchung der elastischen und magnetischen
Eigenschaften einiger Übergangsmetallboride; Note: Magna cum laude
(Sehr gut)
05-06/2016 Forschungsaufenthalt an der University of California Riverside, Department of Chemistry, Riverside, Kalifornien, USA:
Theoretical modelling of Nb7Fe3B8 and Ta7Fe3B8
Seit 02/2018 Wissenschaftlicher Mitarbeiter am Institut für Werkstoff- und Fügetechnik der Otto-von-Guericke Universität Magdeburg
Arbeitsgebiete
Quantenchemie an Festkörpern u.a. Vorhersage der Kristallstruktur, ihrer Stabilität und physikalischer Eigenschaften wie Magnetismus, Härte und andere elastische Eigenschaften, Thermodynamik
Mitgliedschaften
Gesellschaft Deutscher Chemiker