Investigation of the under-vehicle plastic protection parts manufactured by core-back injection process in terms of strength and weight

Year 2023, , 133 - 143, 30.12.2023

Yasemin Gültekin , Mustafa Atakan Akar , Anıl Altındağ , Doğukan Duran , Umut Kumlu

https://doi.org/10.18245/ijaet.1331175

Abstract

Material type, chemical foaming agent, NOx level, core-back distance, and cavity temperature, being the influential parameters in an injection process, significantly affect the weight-based issues and mechanical properties of the resulting product. When the product under inspection is an automotive part, in terms of both the weight and the mechanics are considered to be of high importance. This work is carried out due to a recent task, assigned to NOVARES Engineering and R&D Departments, about the weight reduction of the vehicle underbody plastic protection part (VUPPP), which is located in the rear-lower section of the vehicles. As the core-back process is mostly applied in industry to parts with thickness values of 2.5 mm, the present work involves a challenge due to the fact that before core-back the initial thickness of VUPPP changes between 1.5-1.8 mm. In this study, prototypes are produced with recycled two different polypropylene materials from (PP1 and PP2), two different chemical foaming agents (CFA-X and CFA-Y), six different core-back distances, and two different NOx levels. Finally, laboratory tests are performed on the prototypes to evaluate the weight-based and mechanical features. Experimental data are debated in particular to outline the individual and combined effects of the influential parameters.

Keywords

Core-back process, mold injection, weight reduction, mechanical properties, chemical foaming

Supporting Institution

TÜBİTAK-TEYDEB

Project Number

3190913

Thanks

The authors would like to thank the TÜBİTAK TEYDEB for financial support.

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