Damijan Zorko, Klemen Kolar, Bor Mojškerc, Nikola Vukašinović

Abstract:
The study investigates the effects of various parameters on the root crack propagation and, consequently, the service life of the polymer gear. The international gear design standard ISO 6336 employs the 30° tangent method to determine the tooth’s critical section location. In the first step, the adequacy of the 30° tangent method, was verified by employing a FEM model. In the next step, a novel numerical model was prepared to simulate the growth of a crack located in the root of an observed tooth. The numerical model takes into account the experimental results obtained by performing standard gear tests on a dedicated test bench. Using the numerical model, the effect of the initial crack location, its size and orientation were analyzed.

Keywords:
gears, polymers, fatigue, fracture, failure, crack