The bumper of the car is an accessory of the body part […]
The bumper of the car is an accessory of the body part (wearable part 636f70797a6431333337623431), which is located at the front of the car (called the front bumper) and at the rear of the car (called the rear bumper).moulds for bumper
At present, domestic automobile front and rear bumpers generally use toughened (modified) polypropylene (PP) material as raw material for injection molding-polypropylene Poly (propylene) plastic (commonly known as PP material), with a high melting point (up to 167 ℃), resistant Heat, density (0.90g / cm3), is the lightest of the current general plastics, has high corrosion resistance (tensile strength 30MPa), and its products have relatively good strength, rigidity and transparency, Disadvantages are poor low temperature resistance (composed of three kinds of impact PP copolymer, styrene elastomer and polyolefin rubber blended modified material, with high rigidity, impact resistance, scratch resistance and paintability, injection molding After the molded bumper is loaded, it will not be broken by the impact of 8 km / h, and has the elasticity of recovery. The performance is similar to that of PU, and the cost is reduced by 10% to 20%).
In 1991, Toyota Motor Corporation used nano-PP composite materials for the front and rear bumpers of automobiles, reducing the thickness of the original bumpers from 4 mm to 3 mm, and reducing the quality of the products by about 1/3. Currently, more than 90% of bumper systems in North America are produced using polyolefin-based materials. The annual growth rate of thermoplastic elastomer (TPO) usage in the North American automotive industry exceeds 10%. In 2005, TPO accounted for 75% of the North American plastic bumper market, while the use of RIM and PC / PBT bumpers fell to 20% and 1%.
Some bumpers are made of other materials (such as fiberglass, carbon fiber and other materials), because of their poor environmental performance (recyclable) or high cost, they are not as good as those made of modified PP materials (plastic Equal weight with rigidity, light weight and thinness, and low cost have always been the primary pursuit goals for bumpers), and ordinary PP materials themselves have stable dimensions and poor low temperature resistance, so the materials used to make car bumpers in the next few years It will also be dominated by modified PP materials and increasingly mature thermoplastic elastomer (TPO) production.