The materials used for car bumpers are not fixed; depending on the vehicle model, usage scenario, and technical requirements, they are mainly divided into two categories: plastic and metal. Plastic is currently the mainstream choice for passenger vehicles, especially toughened (modified) polypropylene, blended modified materials, ABS, and PC/ABS. Metal is more often used in older cars or special vehicles to meet the strong protection requirements of specific scenarios. Structurally, car bumpers can be either one-piece molded or segmented. One-piece bumpers are usually made of plastic or fiberglass through injection molding, presenting a continuous appearance. Segmented bumpers, to reduce maintenance costs, are sometimes divided into multiple sections connected by connecting plates and rubber pads, allowing for individual replacement of damaged sections.
Modern car bumper systems are typically part of a layered protection system. The outer plastic bumper acts as a buffer, its energy-absorbing properties cushioning the impact of low-speed collisions. The metal anti-collision beam and energy-absorbing box hidden behind the bumper undertake the main structural energy absorption and protection tasks, together forming the vehicle's safety defense line.