# Assessment of Crash Performance of an Automotive Component Made through Additive Manufacturing
## 1 Introduction
An extensive review that provides a joint perspective on design and structural optimization in additive manufacturing (AM) is available [13], in which a framework was established to highlight the interdependencies between the design for additive manufacturing (DfAM) and structural optimization and the necessity for a holistic approach to structural optimization, which uses lightweight strategies such as topology optimization and/or latticing. The crushing behavior of additively manufactured tubes created using laser powder-bed fusion technology was studied in [14], and their crashworthiness was assessed based on different criteria. In this study, we analyzed the case of frontal impact, the major cause of death and serious trauma compared to other types of accidents, with reference to damage to the lower arms of a passenger in the category of adult occupants. The impact on safety performance of a new glove box constructed using additive manufacturing was estimated, considering two different materials: polyamide (PA) and polypropylene (PP), both reinforced with 5% basalt (to pinpoint this latter aspect, the acronyms become PAB and PPB, respectively). Manufacturing a component with pure thermoplastic materials is inconvenient, as they have poor mechanical properties. To improve their properties, one method is to reinforce the materials with short fibers. Natural basalt fibers were chosen due to their low cost compared to carbon or glass fibers. The currently adopted glove box consisted of two covers, both composed of talc-filled polypropylene, and joined by vibration welding. Due to the intrinsic characteristics of this welding method, which is based on a stamp and a substamp, and which must orient the walls to the mold axis, it is not possible to create complex geometries. Additive manufacturing was therefore chosen because the component produced consists of only one part, so there are no connecting elements such as welds and joints, which weaken the structure mechanically. In principle, any material or combination of materials can be used, and complex geometries, which are more effective under certain load conditions, can be created. There are various additive-manufacturing technologies; in our study, the component was fabricated using the fused deposition model (FDM) technique, the most popular extrusion-based additive manufacturing technology, which forms the components by building them up layer by layer. Figure 1 shows the internal structure of the two boxes in various sections. The internal structure of the additive box is impossible to realize through a traditional molding process due to its high geometric complexity. Another advantage to additive manufacturing could be, in some applications, the reduction of costs. This methodology can be applied to spare parts for premium vehicles, which are generally in low demand. The current production strategy involves increasing the production of spare parts for those vehicles to avoid creating another mold, which increases costs. This strategy's high inventory costs create inefficiencies. For the additive box, no stock is kept in warehouses, and the component is printed only if it is requested.