Cutting weight is not useful everywhere on a vehicle. Too little weight in some locations can impact the driving performance. The underbody, however, is a prime target for weight reduction. Here, manufacturers like to achieve two fuel-saving measures in one go. Firstly, with good aerodynamics. Secondly, by making the part low in weight.
But how much mass can be eliminated here? On average, the underbody systems from FPM are 700 grams per square meter lighter than an injection-molded part. In comparison with glass fiber-reinforced textiles, one saves about 400 grams. Extrapolated to an entire production series, that would amount to several tons of CO2. “No one is lighter today—especially not with this cost-performance ratio,” explains Dr. Alen Nosic, Global Strategic Business Unit Manager Automotive.
This is made possible thanks to a combination of one needle-punched nonwoven layer and two spunbond layers. These are arranged according to the sandwich layer principle, with the needle-punched layer in the middle. The ideal ratio of the layers as well as the individual layers themselves can be adapted to the specific application, such as to achieve even greater stiffness.
The light weight has definitely already proven itself in one of the core purposes, protection against stone impacts: To be entirely certain, the material experts at FPM fired nails and stones at the underbody. The results were gratifying. The nonwoven layers had no problem withstanding the test series.
Additional advantages can be seen in further processing: The material is easy to shape and does not tear at the mounting points. For the workers at the car manufacturer’s assembly line, this means: “They need fewer screws to fasten the underbody, which in turn saves time and money,” says Nosic. Moreover, the nonwoven mixture poses no health risks, in contrast to glass fiber-reinforced materials. In other words, working with the material does not result in risks from fine dust or skin-irritating chips. The best part: The material is recyclable, which opens up new possibilities for sustainable production.
From the perspective of the car owner, it is also worthwhile to have an underbody made of PET on the car. The material has an absorbing effect that reduces the generation of noise in the car interior. Alen Nosic explains: “Sound waves do not penetrate the structures. They are converted into thermal energy instead.”
Stable, quiet, easy to install: Important arguments for a lightweight part in the automotive sector. And the material competence that lies within the underbody paneling also makes possible alternatives to typical materials in other areas.