Jeep and SUVs are often used for off-road driving or particularly poor road conditions, so they need to be equipped with a particularly durable bottom panel. To this end, the company uses Tepex brand continuous fiber reinforced thermoplastic composites created by LANXESS subsidiary Bond-Laminates GmbH to launch an innovative material solution. These new materials will give manufacturers the ability to create indestructible engine hoods, fuel caps, and central flue covers that have been used in multiple standard models such as Bentley Bentayga.
"We tested on uneven and hard test roads, and the components withstood extreme underbody wear and sand impact with little damage," said Tepex application developer Harri Dittmar. In addition, composite materials can simplify the production process. "Custom parts can be produced using the same molds as the corresponding standard automotive parts. There is no need to switch to other materials when processing, avoiding additional mold investment and achieving higher clamping force," Dittmar added.
Simple compression molding process
The shields and covers for standard and custom molds are made from polypropylene-based lightweight thermoplastic reinforcement (LWRT) through a press molding process. A large piece of LWRT blank is heated by a convection oven and inserted into a die by a robot. Depending on the size of the part, a maximum of four parts can be made at the same time. Parts are then stamped from the finished blank or cut by a water gun. To make a component for a custom part, a 0.5 mm thick Tepex insert is placed on the LWRT blank and formed with the blank so that a Tepex surface is formed on the ground-facing side of the final component.
The engine hood and fuel tank cap are made by ElringKlinger Abschirmtechnik AG in Severen, Switzerland, using LWRT material ElroCoustic. The central flue cover is made by Röchling SE & Co. KG in Mannheim, Germany, using an independently developed LWRT material called Seeberlite. The inserts for all custom parts are made of Tepex dynalite 104-RG 601, which contains a polypropylene matrix in which 47% of the continuous glass fiber roving is embedded as a single layer of fiber.
Excellent noise absorption
The upper layer of Tepex significantly improves the strength and stiffness of the LWRT components, and more importantly, also increases the hardness. Dittmar said: "Because of its unique structure, LWRT also has very good sound absorption effects, which cannot be achieved with other compression molding materials, which means that the comfort of the product must be greatly reduced." Outside the side, Tepex material is also coated on the inside surface, then the durability of the composite structure will be further improved. "In the end, a sandwich structure made of LWRT will be formed, which will increase the firmness while keeping the material lightweight," said Dr. Egon Moos, Röchling Automotive Undercarriage Product Manager.
Wide range of applications
Tepex's applications are not limited to automotive floor panels. This innovative material can also be seen in a variety of other applications in automotive lightweight construction. The composite was shaped and re-injected to make seat backs, cowl assemblies, brake pedals and bumper beams. In view of the growing potential of Tepex in the field of lightweight automotive engineering, LANXESS has established a dedicated project team to provide global partners with comprehensive support services from Tepex component development to product launch.