The bumper is a safety device that absorbs and eases the external impact and protects the front and back of the car body. Twenty years ago, the front and rear bumpers of cars were mainly made of metal materials. They were stamped into U-channel steel with a thickness of more than 3mm. The surface was treated with chrome and riveted or welded together with the frame rail. With the development of the automobile industry, the automobile bumper as an important safety device is also on the road of innovation. Today's car front and rear bumpers in addition to maintaining the original protection function, but also the pursuit of harmony and unity with the body shape, the pursuit of its own lightweight. To achieve this purpose, the front and rear bumpers of cars are made of plastic, known as plastic bumpers. The plastic bumper is composed of three parts, such as the outer plate, the cushioning material and the beam. The outer plate and buffer material are made of plastic, and the beam is made of cold rolled sheet with a thickness of about 1.5 mm and is stamped into a U-shaped groove; The outer plate and cushioning material are attached to the beam, which is attached to the frame rail screw and can be removed at any time. This kind of plastic bumper uses the plastic, basically uses the polyester series and polypropylene series of two materials, using the injection molding method. Abroad there is also a kind of plastic called polycarbon ester, infiltration into the alloy composition, alloy injection molding method, processing out of the bumper not only has high strength rigidity, but also has the advantages of welding, and the coating performance is good, the amount of more and more in the car. Plastic bumper has strength, rigidity and decoration, from the safety point of view, the car collision can play a buffer role, protect the front and rear car body, from the appearance, can be naturally combined with the body in a piece, integrated into a whole, has a good decoration, become an important part of the decoration car appearance.
