n insert molding process employing a co-polyamide adhesion promoter to bond aluminum tubing with fiberglass-reinforced polyamide 6 is being used by Mercedes Benz in several of its vehicles to derive weight savings.
The aluminum tubing employed in the vehicles connects both A-pillars together and supports the entire dashboard—from the steering wheel to the glove compartment. These elements used to be welded or screwed together with metal connecting plates, a stable solution, but one that involves more weight.
By contrast, Vestamelt X1333-P1, a co-polyamide from Evonik Industries (Essen, Germany), covers the aluminum tubing and joins the holding brackets (made of fiberglass-reinforced polyamide 6) of the individual components to the tubing by means of an injection molding process based on melt-bonding. When this adhesion promoter is used, component weight can be dramatically reduced by up to 20% compared to conventional solutions.