The lifespan and mechanical properties of polymer materials depend on many factors. When speaking of thermoplastics, which are the most used group of technical polymers (even in gear technologies) due to ease of processing, we must stress a strong temperature dependence. This Masters’ dissertation assesses the effect of physical parameters, especially temperature and load on the lifespan of gears from polyoxymethylene (POM). A special test facility was developed for the purposes of this work, which enabled precise measurements of lifespan and efficiency of the gear pair at a constant, pre-set temperature of the gear tooth base. Based on the test matrix, 12 loading combinations were tested (three load levels and four temperatures) and at the end collected into temperature-dependent S-N diagrams. Results show that higher temperature drastically affects the lowering of transfer efficiency and the shortening of the lifespan of POM gears.
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