1. ZHAW digitalcollection
2. School of Engineering
3. Publikationen
4. Publikationen School of Engineering

Publication type:	Conference paper
Type of review:	Peer review (abstract)
Title:	Fatigue lifetime analysis of POM gears for generalized tooth root loading and shapes
Authors:	Eberlein, Robert Düzel, Sven
et. al:	No
Conference details:	39th International Conference of the Polymer Processing Society (PPS-39), Cartagena de Indias, Colombia, 19-23 May 2024
Issue Date:	2024
Language:	English
Subject (DDC):	620: Engineering
Abstract:	Today, commonly used calculation methods for the determination of the tooth root load capacity of polymer gears (e.g. VDI 2736) are based on the same assumptions as for steel gears. Due to the widely varying material properties of polymers in terms of non-linear material behavior and rate dependency, the predicted lifetimes of polymer gears are inaccurate [1]. In a previous study, rate-dependent nonlinear viscoplastic finite element (FE) modeling of POM allows the quantification of material influences that are not considered in standard assumptions for metal parts [2]. Based on a physically motivated material model, a lifetime model was developed and validated to predict tooth root fracture as a function of rotational speed. In the present study, the existing lifetime model is extended and validated to include the torque (tooth loading) and notch (tooth root shape) dependency. It is found that a cyclic increase in the cumulative strain energy density occurs in the polymer gear tooth root, as can be investigated for uniaxial loading [3]. This strain energy density can be used as a damage variable that causes crack initiation and leads to tooth root fracture. Using the lifetime model, the evolution of the damage variable(s) can be predicted to derive a critical level of loading cycles, thus forming a damage criterion. Numerical results show that the damage criterion is independent of speed, load and geometric influences, whereas the validity of the damage criterion is proven by comparison with experimental results obtained from a gear test bench.
Further description:	References: [1] A. Pogačnik, and U. Kissling, “The future of plastic gear standardization,” 2022, pp. 1149–1160. doi: https://doi.org/10.51202/9783181023891 [2] S. Düzel, R. Eberlein, and H.-J. Dennig, ”Fatigue life analysis of POM gears with transient material modelling”, accepted for publication in AIP Conf Proc, 2023 [3] R. Shrestha, J. Simsiriwong, and N. Shamsaei, “Fatigue modeling for a thermoplastic polymer under mean strain and variable amplitude loadings,” Int J Fatigue, vol. 100, pp. 429–443, Jul. 2017, doi: 10.1016/j.ijfatigue.2017.03.047
URI:	https://digitalcollection.zhaw.ch/handle/11475/30333
Fulltext version:	Published version
License (according to publishing contract):	Licence according to publishing contract
Departement:	School of Engineering
Organisational Unit:	Institute of Mechanical Systems (IMES)
Appears in collections:	Publikationen School of Engineering

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.