In-situ wear-progression measurement in POM-steel gear contacts

Osolnik, Nejc (author), Kalin, Mitjan (author)

Wear is the dominant failure mechanism in polymer–steel gear pairs. This study presents an in-situ optical method for measuring the wear-progression of a polyoxymethylene (POM) gear meshing with a steel pinion on a real-scale gear test rig under controlled operating conditions. The method enables imaging of the individual teeth without removing the gears from their operating environment. Experiments were performed for a range of operating parameters (torque: 1/2 Nm, rotational speed: 1200/1800 rpm, temperature: 30/70 ◦C). The in-situ profiles reveal three distinct wear regimes: (1) a running-in phase with nearly uniform material removal and a steep decrease in the wear coefficient during the first 30,000 load cycles, (2) a position-dependent regime dominated by dedendum and tip wear with delayed wear in the pitch area, and (3) a steady-state regime where wear progresses approximately linearly at all characteristic flank positions. Contact analyses using imported measured profiles show a redistribution of the contact pressure toward the pitch area, consistent with the observed transition to steady-state wear. Higher torque and speed reduce the number of cycles to the wear-failure criterion, whereas a higher temperature extends the lifetime and promotes a more uniform flank engagement for the investigated material pairing and operating conditions. Scanning electron microscopy (SEM) observations support a milder wear morphology at 70 ◦C compared to 30 ◦C. The method provides time- and position-resolved wear data that are difficult to reconstruct from ex-situ techniques and is suitable for supporting flank wear modeling and optimization.

• Language: English
• Keywords: polymer gears, wear-progression, wear mechanisms, in-situ measurement, optical imaging
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FS - Faculty of Mechanical Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2026
• Number of pages: 13 str.
• Numbering: Vol. 594, art. 206674
• PID: 20.500.12556/RUL-181298
• UDC: 539.92:621
• ISSN on article: 1873-2577
• DOI: 10.1016/j.wear.2026.206674
• COBISS.SI-ID: 273713155
• Publication date in RUL: 31.03.2026

Record is a part of a journal

• Title: Wear
• Publisher: Elsevier
• ISSN: 1873-2577
• COBISS.SI-ID: 23274757

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: polimerni zobniki, napredovanje obrabe, mehanizmi obrabe, in-situ merjenje, optično slikanje

Projects

• Funder: ARIS - Slovenian Research and Innovation Agency
• Project number: P2-0231
• Name: Tribologija