Is it a car manufacturer to cut corners with plastic instead of metal bumpers?
Why is the bumper plastic? Isn't iron more durable? The reason is simple, but the truth is very profound! The early front and rear bumpers of the car were mainly made of metal materials. The first plastic bumper used was Fiat. From then on, other car companies followed suit. Because of the many advantages of plastic bumpers, let's take a look at the advantages of plastic bumpers.
First, it is light in weight. First of all, the weight of the plastic bumper is lighter than that of iron or other materials, which also reduces the weight of the whole vehicle, and the car is not heavier and safer. Now many car manufacturers are The weight of the car is reduced, the weight is down, and the fuel consumption is naturally reduced.
The second is to cushion when colliding. When the car is driving at low and medium speeds, if it collides with other vehicles or objects, the plastic bumper can also play a certain buffering effect. Even if the car hits the pedestrian, the bumper will absorb most of the deformation. The energy, so it will be less harmful to people.
The third is easy to repair. Car maintenance is also a big expense. If it is not in the case of a small bump, the plastic bumper can automatically rebound and automatically repair, even if it is painted, it is always stronger than the recess. After all, the paint is much cheaper than the sheet metal repair.
Plastic bumpers used by automakers are not cut corners. Although they are fragile, they do not mean that they are unsafe. Plastic bumpers not only benefit passengers in the car, but also protect pedestrians in the event of a car accident.
Comparison of material selection of bumpers
When selecting materials, PC, PBT, and modified PP materials are provided as the main selection targets according to the performance requirements of the bumper.
Excellent overall performance, especially outstanding impact resistance, transparency and dimensional stability, excellent mechanical strength and electrical insulation, a wide temperature range (-60 - 120 ° C).
PBT is one of the toughest engineering thermoplastics. It is a semi-crystalline material with excellent chemical stability, mechanical strength, electrical insulation properties and thermal stability. These materials are very stable under a wide range of environmental conditions.
The PP material is a modified polypropylene. The polypropylene has high crystallinity and regular structure, and thus has excellent mechanical properties. The absolute value of the mechanical properties of polypropylene is higher than that of polyethylene, but it is still a low grade in plastic materials, and its tensile strength can only reach 30 MPa or slightly higher.