Oct 6 2008
Sika Automotive has selected BASF’s Ultramid® A3WG10 CR to manufacture a bodywork insert for use in the new Peugeot 308 sw. This plastic belongs to BASF’s new class of special polyamides that have been optimized for high durability and strength.
The component consists of Ultramid® CR (gray) and the struc¬tural foam SikaReinforcer® (yellow)
The elaborate mechanical characterization of these materials is integrated into BASF’s Integrative Simulation, thus making it possible to safely develop highly loaded parts directly on the computer. The structural insert installed on the tailgate hinge of the station wagon is a hybrid component consisting of a plastic skeleton, two metal tabs and the structural foam SikaReinforcer®, which joins the system to the bodywork. This insert serves to reinforce the structure and it has to absorb the exerted forces as well as contribute to local stiffening.
This Peugeot plastic insert developed by Sika is shaped in a two-component injection-molding process that first creates a high-strength plastic support and then encapsulates it with SikaReinforcer. The component is attached to the bodywork by means of welding bridges, subsequently passing through cleaning and priming baths together with the car body. Only when exposed to heat in the drying installation does the structural foam expand and harden, thus firmly joining the plastic structural insert to the surrounding parts. Before this component went into serial production, BASF calculated its strength and failure behavior by Integrative Simulation. Via real flexural and fracture tests the computer prediction was exactly confirmed. This approach considerably enhances the safety of the component.
The plastic
Ultramid A3WG10 CR is a chemical-resistant plastic reinforced with 50% glass fibers. In contrast to similar conventional PA66 types, it absorbs a great deal of energy, accounts for very high strength and stiffness, even at elevated temperatures, and is thus suitable for high dynamic loads. In this context, it has also been optimized with respect to its crash behavior. The material was also utilized for the recently introduced torque rod supports which are being made of plastic for the first time and which were developed and manufactured by ContiTech Vibration Control.
Simulation of structural foams
As showcased for the first time at the K 2007 plastics trade fair, BASF has developed a material model for structural foams and implemented it in its program system for Integrative Simulation. On the basis of this knowledge, numerous structural components can now be designed that are joined by means of foams, enabling them to meet high requirements in terms of strength, static load-bearing capacity and crash safety.
Cooperation between Sika Schweiz AG and BASF SE
BASF and Sika Schweiz have entered a colaboration for the development of structural stiffeners. The combination of Ultramid materials and the joining technology in the form of the SikaReinforcer structural foam translates into highly efficient yet lightweight stiffening components. The two companies are jointly developing components, all the way from the concept and the prototypes to serial production.