AEA – Brazilian Society of Automotive Engineering - SIMEA 2021 (Allowed reproduction with source m ention:AEA) – Sim pósio Internacional de Engenharia Automotiva – SIMEA 2021 – São Paulo, Brasil Evaluation of PETG mechanical behavior for application in vehicle protection Gabriel Martins de Castro Universidade de Brasília – campus Gama. Engenharia Automotiva Rita de Cássia Silva Universidade de Brasília – campus Gama. Engenharia Automotiva Alessandro Borges de Sousa Oliveira Universidade de Brasília – campus Gama. Engenharia Automotiva ABSTRACT During the last decades, highway authorities and motor vehicle manufacturers attempt to reduce the statistics of accidents in the world. However, the number of road traffic deaths continues to rise steadily, reaching 1.35 million in 2016. One of the accidents present in this statistic is the side- impact. Several researchers have dedicated themselves to develop passive safety devices that meet the demand for protection of the occupants in the event of collisions. Thin- walled energy absorbers are currently used to protect vehicle passengers against the harmful consequences of frontal collisions; though, the idea of using them against side impacts has not been appropriately explored. This work aims to present the experimental tests performed on the material PETG (polyethylene terephthalate glycol), a semicrystaline thermoplastic. The ASTM C365 covers the determination of compressive strength and modulus of sandwich cores, under quasi-static compressive loads. ASTM D638 reports the procedure to determine the tensile properties. The results draw that the material could have a significant contribution to resisting the impact, whether applied as a core of a thin- walled square mild-steel tube. Keywords: Safety, PETG, Compression test, Tension test INTRODUCTION Energy-absorption systems are of considerable interest to automotive and aerospace engineering. During the years, many researchers have highlighted the effectiveness of these structures in dissipating impact energy by a stable progressive collapse mode when subjected to axial compressive loads. Alghamdi (2001) [1] presented a review about thin- walled tubes demonstrating that these structures are the most widespread shape of collapsible impact energy absorbers. For this purpose, he showed about a hundred of references concerning this subject. Shindle and Mali (2018) [2] treated this topic focusing on the crushing behavior of energy absorbers covering about sixty-eight references related to metallic energy absorbers, and the application of composite tubes, fiber metal lamination (FML) member and honeycomb plate as a mean of impact protection. The energy absorption capability of composite materials has mainly been studied in the last years. The research on composite materials has advanced because of their higher capacity of absorbing energy, adding low weight to the structure [3, 4]. The main composites identified to crash absorber are fiber-reinforced plastic (carbon fiber polymer [5], fiberglass [4, 6], and Kevlar [6], for instance) and foam (polyurethane [7], aluminum foam [8]). In terms of structural design, multi-cells thin-walled tubes have been performed better compared to single thin- walled tubes. Many researchers have indicated in their researches such a behavior [8, 9, 10]. However, its industrial production may not be simple to achieve [11]. Another way to improve the crashworthy ability of energy absorbers is to fill on the tubes with honeycomb structures [12]. These structures have the geometry of a honeycomb to minimize weight and cost. The geometry can vary, but the usual shape is hexagonal, forming hollow cells between thin plates. The present work aims to present the experimental tests performed on the material PETG (polyethylene terephthalate glycol), a semicrystaline thermoplastic. The PETG composite is one of the most consumed material in 3- D printing fused deposition modeling method (FDM). This material presents a significant balance between strength and ease of printing. Besides, it has good shock resistance, and, in this work, it does not have any addition. Moreover, the PETG glass transition temperature is 85 g T   . It represents the range of temperature where the polymer substrate changes from a rigid glassy material to a soft (not melted) [13]. The melting temperature is about 260º. Thus, at a temperature of 60º C, this polymer will be about 70% of its glass transition temperature, consequently, in its glassy