PSI - Issue 19

Available online at www.sciencedirect.com Available online at www.sciencedirect.com Available online at www.sciencedirect.com

ScienceDirect

Procedia Structural Integrity 19 (2019) 645–654 Structural Integrity Procedia 00 (2019) 000–000 Structural Integrity Procedia 00 (2019) 000–000

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© 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Fatigue Design 2019 Organizers. Abstract Due to their high specific properties, fiber reinforced plastics are ideal candidates for the substitution of steel parts in the automotive sector enabling high weight savings and increasing the e ffi ciency of automobiles. One possible application are leaf springs made of glass fiber reinforced plastics. Due to the simple bending load case, the fiber orientation can be aligned with the main stress direction. In real life such components as leaf springs are loaded under stochastic loads originated from di ff erent driving maneuvers. To replicate those fatigue load case, a high number of component tests are required. Aim of the present work (as a result of a joint research project between the Institute for Plastics Processing and Ford Motor Company) is to develop a simplified testing program that is able to reproduce the damage and the fatigue behavior which occurs in real composite components. For this purpose, three point bending experiments on unidirectional specimens made of glass fiber reinforced epoxy pre-preg material are performed. However, since the loading of the real component introduces additional transverse stresses in the region of the clamping group, the results on specimen level are not transferable to component level. For this purpose, a special clamping group is developed on specimen level to enable a better prediction of fatigue life and the transferability of the results of the fatigue tests to component level. This results in a more realistic representation of the leaf spring stress state in the fatigue experiments. As a result of this research, a higher safety margin in the design phase of such components and less testing time is achieved. c 2019 The Authors. Published by Elsevier B.V. r-review unde responsibility of the Fatigue Design 2019 Organizers. Keywords: Glass fibre reinforced plastics; leaf spring; fatigue; damage Fatigue Design 2019 Fatigue testing of FRP aterials for the application in auto otive leaf springs Fabian Becker a, ∗ , Christian Hopmann a , Francesco Italiano b , Alberto Girelli b a Institute for Plastics Processing, RWTH Aachen University, Se ff enter Weg 201, Aachen, 52074, Germany b Ford Research and Innovation Center, Su¨sterfeldstraße 200, Aachen, 52072, Germany Abstract Due to their high specific properties, fiber reinforced plastics are ideal candidates for the substitution of steel parts in the automotive sector enabling high weight savings and increasing the e ffi ciency of automobiles. One possible application are leaf springs made of glass fiber reinforced plastics. Due to the simple bending load case, the fiber orientation can be aligned with the main stress direction. In real life such components as leaf springs are loaded under stochastic loads originated from di ff erent driving maneuvers. To replicate those fatigue load case, a high number of component tests are required. Aim of the present work (as a result of a joint research project between the Institute for Plastics Processing and Ford Motor Company) is to develop a simplified testing program that is able to reproduce the damage and the fatigue behavior which occurs in real composite components. For this purpose, three point bending experiments on unidirectional specimens made of glass fiber reinforced epoxy pre-preg material are performed. However, since the loading of the real component introduces additional transverse stresses in the region of the clamping group, the results on specimen level are not transferable to component level. For this purpose, a special clamping group is developed on specimen level to enable a better prediction of fatigue life and the transferability of the results of the fatigue tests to component level. This results in a more realistic representation of the leaf spring stress state in the fatigue experiments. As a result of this research, a higher safety margin in the design phase of such components and less testing time is achieved. c 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Fatigue Design 2019 Organizers. Keywords: Glass fibre reinforced plastics; leaf spring; fatigue; damage Fatigue Design 2019 Fatigue testing of GFRP materials for the application in automotive leaf springs Fabian Becker a, ∗ , Christian Hopmann a , Francesco Italiano b , Alberto Girelli b a Institute for Plastics Processing, RWTH Aachen University, Se ff enter Weg 201, Aachen, 52074, Germany b Ford Research and Innovation Center, Su¨sterfeldstraße 200, Aachen, 52072, Germany

1. Introduction 1. Introduction

The trend towards e-mobility and higher e ffi ciency of motor vehicles requires lightweight constructions. One pos sible solution is the replacement of steel leaf springs with parts made of fiber reinforced plastics (FRP). Mass savings up to 60 % compared to steel are possible (Meatto et al. (1999)). Further advantages are the higher material damping properties and the avoidance of corrosion issues compared to a steel component. Due to the high strain to failure, glass The trend towards e-mobility and higher e ffi ciency of motor vehicles requires lightweight constructions. One pos sible solution is the replacement of steel leaf springs with parts made of fiber reinforced plastics (FRP). Mass savings up to 60 % compared to steel are possible (Meatto et al. (1999)). Further advantages are the higher material damping properties and the avoidance of corrosion issues compared to a steel component. Due to the high strain to failure, glass

2452-3216 © 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Fatigue Design 2019 Organizers. 10.1016/j.prostr.2019.12.070 ∗ Corresponding author. Tel.: + 49-241-80-93806 E-mail address: fabian.becker@ikv.rwth-aachen.de 2210-7843 c 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Fatigue Design 2019 Organizers. ∗ Corresponding author. Tel.: + 49-241-80-93806 E-mail address: fabian.becker@ikv.rwth-aachen.de 2210-7843 c 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Fatigue Design 2019 Organizers.