doc. dr. Marko Polajnar
Short biography
Assist. Prof. Dr. Marko Polajnar is researcher in the field of tribology, with a particular focus on elastohydrodynamic (EHD) lubrication, wetting and solid-liquid interface phenomena. His research integrates experimental tribology, surface science, and interface nanoengineering to understand and optimize lubrication and frictional behavior in highly demanding mechanical contacts.
He has made significant contributions to the understanding of solid–liquid interface effects in EHD contacts, demonstrating interaction between surfaces and lubricants can be used to reduce friction and energy losses. His postdoctoral project InterEHL (2019–2021) introduced a novel approach to EHD contact design by employing different additives to tailor surface energy of steel surfaces to reduced full-film EHD friction.
Dr. Polajnar’s research combines fundamental and applied aspects, resulting in collaborations with major international industrial partners such as TOTAL, OERLIKON SOREVI and Aramco, where his expertise contributed to the development of high-performance lubricants, coatings, and tribological systems. His coordination and participation in Domestic and European application-oriented research projects—including SiNACERDI (automotive brakes), GreenSTAMP (stamping production process), BiLaTex (Ti/Hap implants) reflect his growing influence also in the real engineering and biological applications of the tribology.
In academia, he serves as Assistant Professor at the Faculty of Mechanical Engineering, University of Ljubljana, where he leads and teaches several undergraduate courses in Maintenance, Drives, Aircraft Maintenance. He has supervised numerous bachelor’s and master’s students and supervise three PhD students.
Dr. Polajnar is an active member of the European tribological community, serving on the organizing and scientific committees of several international conferences, including EcoTrib, SloTrib, and PolyTrib. He has acted as guest editor and reviewer for leading international journals such as Lubrication Science and Wear. His scientific achievements are supported by over 40 international and domestic conference contributions, multiple invited lectures, and co-authorship in books and engineering handbooks such as Kraut’s Handbook of Mechanical Engineering.
Dr. Polajnar was awarded the Prešeren Faculty Award and the Faculty Award for International Research Promotion, acknowledging his early scientific excellence and active engagement in international research dissemination.
In addition to his academic activities, Dr. Polajnar has pursued advanced training abroad, including the MIT Professional Education Programme in Tribology: Friction, Wear, and Lubrication (Boston, USA, 2023, 1 week) and a visiting research fellowship at Imperial College London (UK, 2025, 7.5 months).
Bibliography in short
- Assistant Professor at the Faculty of Mechanical Engineering, University of Ljubljana
- Education: B.Sc. (2010) and Ph.D. (2015) in Mechanical Engineering, University of Ljubljana
- Research areas: Tribology, EHD lubrication, wetting and interfacial phenomena, green tribology, surface nanoengineering, bio-tribology (implants, tooth wear), application-oriented tribology (stamping, brakes).
- Publications: 18 scientific papers
- Invited lectures: 5 at international conferences (Germany, Japan, Italy, Croatia)
- Conference contributions: Over 40 presentations worldwide
- Book chapters: Co-author of chapters in Kraut’s Handbook of Mechanical Engineering and Explanatory Dictionary of Mechanical Engineering, Co-author of the chapter in book Applications of diamond-like carbon coatings
- Industrial reports: Over 20 for national and international companies
- Research projects: Collaboration in 5 domestic and international projects
- Conference and editorial activity: Member of scientific and organizing committees of EcoTrib, SloTrib, PolyTrib; Guest Editor of Wear (Special Issue, 2017–2018)
- Teaching and mentorship: Developer and lecturer of new courses Maintenance, Drives, Aircraft Maintenance; mentor/co-mentor to 18 students
- Awards: Prešeren Faculty Award (2010), Faculty Award for International Research Promotion (2013)
- International training and visits: MIT (Boston, USA, 2023, 1 week), Imperial College London (London, UK, 2025, 7.5 months)
Reference Projects:
- PATRON - The Doctoral Network on Prognostics and heAlth management of nexT GeneRatiOn drivetraiNs (2024 - 2028)
- BiLaTex - New generation of bioactive laser textured Ti/HAP implants (2023 - 2026)
- InterEHL - Novel design of EHL contacts by employing solid-liquid interface phenomena (2019 - 2021)
- GreenSTAMP - Nano-engineered Green lubrication technology for sustainable high-performance stamping (2018 - 2021)
- E-maintenance of electro-mechanical drives: prognostics and health management solutions under non-stationary operating conditions (EMAINT) (2016 - 2019)
- MATERA SiNACERDI - Nanostructured composite materials and reinforced ductile iron for high wear applications (2011 - 2014)
Publications
- The surface-topography challenge : a multi-laboratory benchmark study to advance the characterization of topography
PRADHAN, A., MÜSER, M. H., MILLER, N., ABDELNABE, J. P., AFFERRANTE, L., ALBERTINI, D., ALDAVE, D. A., ALGIERI, L., ALI, N., ALMQVIST, A., KALIN, Mitjan, POLAJNAR, Marko, POŽAR, Tomaž, SAMODUROVA, Anastasia, et al. , Tribology letters. 2025, vol. 73, art. no. 110, str. 1-26 - Analysis of different guide elements’ designs in hydraulic cylinders
J. Pustavrh, A. Trajkovski, V. Tič, M. Polajnar, U. Bohinc, F. Majdič, Applied sciences. April 2025, vol. 15, iss. 9 - Effect of laser surface texturing and fabrication methods on tribological properties of ti6al4v/hap biocomposites
J. Sadlik, M. Polajnar, R. Kumar, M. Kalin, G. Kravanja, L. Hibar et al., Materials. 2025, vol. 18, issue 11, 27 str. - Laboratory tribological screening test methodologies to evaluate the performance of metalworking lubricants for punching stamping
M. Polajnar, L. Čoga, S. K. Sharma, M. Kalin, Tribology international. 2025, vol. 211, 110815, 14 str. - Tribological properties of steel sheet with epoxy-based enamel coating under dry and lubricated conditions for stamping applications
L. Čoga, M. Polajnar, A. Samodurova, M. Kalin, Journal of Materials Research and Technology. May-Jun. 2025, vol. 36, str. 7666-7675 - Perfluorotetradecanoic Acid as an Additive for Friction Reduction in Full-Film EHD Contacts: The Role of Functional Group, Base Oil Polarity, Additive Concentration and Contact Pressure
M. Polajnar, T. Požar, M. Kalin, Lubricants 2025, 13(6), 263 - Perfluorocarboxylic acids as additives for friction reduction in full-film EHD contacts: Influence of additive chain length
M. Polajnar, T. Požar, M. Kalin, Tribology International, Volume 211, November 2025, 110892 - Wear of hydraulic pump with real particles and medium test dust
N. Novak, A. Trajkovski, M. Polajnar, M. Kalin, F. Majdič, Wear 532-533 (2023) 205101 1-13 - Base lubricants for green stamping: The effects of their structure and viscosity on tribological performance
M. Polajnar, L. Čoga, M. Kalin, Friction 11 (2023) 1741-1754 - Study on the influence of interfacial slip on the lubrication performance of a step slider bearing
Z. G. Jing, F. Guo, W. Jin, M. Kalin, M. Polajnar, Tribology International 176 (2022) 107822 1-9 - Elasto-hydrodynamic friction changes on steel surfaces arising from the modified surface energy of the steel due to additive boundary films
M. Polajnar, B. Thiebaut, F. Jarnias, M. Kalin, Tribology international 164 (2021) 107203 1-10 - Green Tribology for the Sustainable Engineering of the Future
M. Kalin, M. Polajnar, M. Kus, F. Majdič, Strojniški vestnik - Journal of Mechanical Engineering 65 (2019) 11-12, 709-727. - Friction and wear performance of functionally graded ductile iron for brake pads
M. Polajnar, M. Kalin, I. Thorbjornsson, J.T. Thorgrimsson, N. Valle, A. Botor-Probierz, Wear 382–383 (2017) 85–94. - High‐speed optical imaging of liquid film flow and liquid macro‐slip over free surfaces with different surface energies
M. Polajnar, B. Bizjan, B. Širok, M. Kalin, Lubrication Science (2017) 0: 1-10. - Effect of the slide-to-roll ratio and the contact kinematics on the elastohydrodynamic friction in diamond-like-carbon contacts with different wetting behaviours
M. Polajnar, M. Kalin, Tribology Letters 60 (2015) 1-10. - The wetting of steel, DLC coatings, ceramics and polymers with oils and water: The importance and correlations of surface energy, surface tension, contact angle and spreading
M. Kalin, M. Polajnar, Applied Surface Science 293 (2014) 97-108. - The Effect of Wetting and Surface Energy on the Friction and Slip in Oil-Lubricated Contacts
M. Kalin, M. Polajnar, Tribology Letters 52 (2013) 185-194. - The correlation between the surface energy, the contact angle and the spreading parameter, and their relevance for the wetting behaviour of DLC with lubricating oils
M. Kalin, M. Polajnar, Tribology International 66 (2013) 225-233. - more
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