2. Institute
  3. Staff
  4. Stefanie Hoja
PD Dr.-Ing. habil.

Details

PD Dr.-Ing. habil. Stefanie Hoja

Team Leader

Departments: Materials Science

Phone
+49 421 218 51395
Email
shoja@iwt-bremen.de
Office
Leibniz-Institut für Werkstofforientierte Technologien - IWT
FZB - Room 2490
Badgasteiner Str. 3
28359 Bremen
     

Personal data

Research profiles

• Stress-appropriate nitriding and nitrocarburizing of ferrous materials
• Preheating treatment and tempering effects during nitriding
• Methods for characterizing the compound layer
• Energy efficiency through a combination of surface and surface layer processes
• Wear and fatigue behavior of surface layer composites
• Nitriding of non-ferrous metals for hydrogen applications


Academic education with degree

10/2001 – 01/2007

Chemistry degree with diploma (Dipl.-Chem.) in the Faculty of Biology/Chemistry at the University of Bremen

Topic of the diploma thesis: Analysis of the effect of alternative corrosion inhibitors on the corrosion of the Al alloys Al-2024 and Al-7075 in aqueous chloride-containing media

Supervisor Prof. Swiderek


Wissenschaftliche Abschlüsse

05/2018 – 05/2023

Habilitation (venia legendi Materials Engineering) in the Department of Production Engineering at the University of Bremen

Topic of the habilitation thesis: Nitriding and nitrocarburizing of gears

Reviewers: Prof. Fechte-Heinen (University of Bremen), Prof. Broeckmann (RWTH Aachen), Prof. Rezwan (University of Bremen)
 

01/2012 – 08/2017 

Doctorate (Dr.-Ing.) in the Department of Production Engineering at the University of Bremen

Topic of the dissertation: Forging-compatible nitrided dies

Supervisor: Prof. Hoffmann

Offices and Memberships

Since 03/2022Head of the AWT seminars "Nitriding and nitrocarburizing in practice", "Plasma nitriding and nitrocarburizing", "Component cleaning"
 
06/2021 – 06/2023Head of the AWT hardening group Bremen
 
Since 01/2020Chairwoman of the AWT technical committee 3 Nitriding and nitrocarburizing
 
05/2018 - 09/2023Women's Representative of the Leibniz Institute for Materials Engineering – IWT

Latest 10 publications

  • Hoja, S., Brandt, M., Hunkel, M., Fechte-Heinen, R. 2024.
    Austempering as a Sustainable and Efficient Alternative to QT Treatment in Nitriding of Heat Treatable Steels - Influence of different Bainitic Pretreatment Structures on the Nitriding Response of EN42CrMo4 and EN31CrMoV9. 4th Mediteranean Conference on Heat Treatment and Surface Engineering, Lecce, Italy, 17.-19.04.2024. Lecce, Italy: 2024,
  • Hoja, S., Guba, N., Haupt, N., Surm, H., Hüsemann, T. 2024.
    Investigation of Dimensional and Shape Changes in Combined Surface Layer Heat Treatments of Gear Components Made of EN31CrMoV9 and EN42CrMo4. HTM Journal of Heat Treatment and Materials. 79 (4), 161-183. DOI: 10.1515/htm-2024-0014. OPEN ACCESS
  • Sommer, M., Sitzmann, A., Hantzsche, K., Tobie, T., Stahl, K., Fechte-Heinen, R., Hoja, S. 2024.
    Optimized Compound Layer Design for Highly Loaded Nitrided Gears. Journal of Materials Engineering and Performance. , DOI: 10.1007/s11665-024-09659-1. OPEN ACCESS
  • Hoja, S. 2023.
    Nitrieren und Nitrocarburieren von Verzahnungen.
  • Hoja, S. 2023.
    Bauteilreinigung in Härtereien. HTM-Praxis, HTM Journal of Heat Treatment and Materials. 78 (5), A32-A58. DOI: 10.1515/htm-2023-2011.
  • Hoja, S., Baustert, R., Hasselbruch, H., Steinbacher, M., Fechte-Heinen, R. 2023.
    Investigation of combined surface treatments and coatings to increase the wear behavior of heat treatable steels. Surface and Coatings Technology. 472 , DOI: 10.1016/j.surfcoat.2023.129929. OPEN ACCESS
  • Hoja, S., Birjandi, B. K., Hasselbruch, H., Epp, J. 2023.
    An Investigation into the Wear Behavior of Martensitically Transformed Nitrided Layers. Lubricants. 11 (11), DOI: 10.3390/lubricants11110481. OPEN ACCESS
  • Hoja, S., Karlsohn, M., Hunold, O., Rohde, J., Baumann, J., Boßlet, J., Waldenmaier, T. 2023.
    Die Zukunft der Wärmebehandlungsverfahren – Nitrieren und Nitrocarburieren.. AWT-Info / HTM Journal of Heat Treatment and Materials. 78 (4), A5-A31. DOI: 10.1515/htm-2023-2007.
  • Geitner, M., Zornek, B., Hoja, S., Tobie, T., Stahl, K. 2023.
    Material Influence on the Micropitting and Wear Resistance of Nitrided External and Internal Gears. HTM Journal of Heat Treatment and Materials. 78 (6), 319-340. DOI: 10.1515/htm-2023-0030. OPEN ACCESS
  • Skalecki, M., Sommer, M., Steinbacher, M., Hoja, S. 2023.
    Mechanism and Observation of Pore Formation during Carbonitriding. HTM Journal of Heat Treatment and Materials. 78 (2), 105-118. DOI: doi:10.1515/htm-2022-1028.