Lanxess equips SUVs with Tepex dynalite underbody paneling

The Tepex dynalite-branded continuous fiber-reinforced thermoplastic (CFRTP) composite materials from Lanxess (Cologne, Germany) have proven themselves in the automotive industry as a lightweight material solution for highly effective and mechanically stable underbody paneling components, the company recently reports. The most recent applications can be found in the Li L9 and newly launched Li L8 car models from Li Auto Inc., a Chinese carmaker offering vehicles with alternative drive technologies.

Both of the six-seat, premium family SUVs are plug-in hybrid vehicles and are equipped with underbody paneling components to protect the tank. The large panels consist of a robust, thermoplastic composite structure; specifically, they are compression molded with a reinforcing insert made of Tepex dynalite and a direct long fiber thermoplastic (DLFT) mass.

“The underbody paneling component is around 30% lighter than the comparable steel design. Compared to other material concepts — such as pure DLFT — the Tepex reinforcement makes the paneling component stronger as well as more rigid and energy-absorptive,” Deniz Guerkan, a Lanxess expert in the field of technical marketing and sales for Tepex in Hong Kong, notes. “This means that it is much more resistant to stone impacts or other damages when the vehicle underside hits objects on the road surface.”

The underbody paneling component is around 1.5 meters long, 1 meter wide and 3-4 millimeters thick. It is manufactured with a 1-millimeter-thick insert made from Tepex dynalite 104-RG600 and an additional extruded DLFT mass. Both materials are heated, plasticized and placed in a compression tool, where they are molded together in a single step. The Tepex insert matrix is polypropylene, reinforced with 47 volume percent of continuous glass fiber rovings. The polypropylene DLFT mass contains 40 weight percent of long glass fibers.

According to Lanxess, this material combination reliably fulfills the high mechanical requirements and shows, in particular, a high level of resistance to penetration. The underbody paneling component can be manufactured on a conventional compression molding tool. “This ensures efficient production,” Guerkan says. “The fact that DLFT can be manufactured economically as a direct extrudate, and makes up the majority of the component, also helps to improve cost efficiency.”

Lanxess believes that underbody paneling components featuring a Tepex composite design offer large potential in vehicles equipped with new drive technologies because they are a lightweight alternative to equivalent steel and aluminum components.

“For example, electric vehicle batteries are especially vulnerable because they are usually installed in the floor panel,” Guerkan adds. “Therefore, we are looking at underbody paneling components which protect the batteries against stone impacts or other damages when the vehicle underside gets hit. In the same way, the lightweight Tepex underbody paneling components could be used in hydrogen-powered vehicles to protect the tanks and fuel cells.”