What is the material of a car bumper?
2 Answers
Car bumpers are made of plastic, commonly referred to as plastic bumpers. The outer panel and cushioning material are made of plastic, while the crossbeam is formed by stamping a 1.5mm-thick cold-rolled sheet into a U-shaped channel. The outer panel and cushioning material are attached to the crossbeam, which is then connected to the vehicle frame's longitudinal beams via screws. The plastic used for these bumpers primarily consists of polyester-based and polypropylene-based materials, manufactured through injection molding. Internationally, there is also a type of plastic called polycarbonate-based, which incorporates alloy components and is produced using alloy injection molding. This method results in bumpers that not only exhibit high rigidity but also offer the advantage of being weldable. Consequently, their usage in passenger vehicles is increasingly widespread.
Most car bumpers are made of plastic, particularly that rigid polypropylene material, because it's lightweight, cost-effective to manufacture, and easily molded into various streamlined designs. In minor collisions, it absorbs impact forces, protecting both vehicle occupants and the chassis frame, unlike old-fashioned steel bumpers which were more prone to damaging internal structures or pedestrians. Maintenance is convenient – after scratches, just repaint or replace the entire component, a common job at repair shops. However, plastic materials may age and crack over time, affecting appearance and safety, so regular inspections are necessary to ensure no cracks or corrosion.