World’s first top mount with polyurethane bearing and polyamide housing

• Top mount is 25% lighter than aluminum die-cast version with rubber
• 50% glass fiber reinforced PA66 particularly suitable for dynamic loads
• Right material mix is decisive

BASF provides car manufacturers with a new way to combine weight savings, pleasant acoustics and vibration damping. A unique NVH (noise, vibration, harshness) combination is made possible by combining two of BASF’s plastic materials: the micro-cellular polyurethane elastomer Cellasto and the highly glass-fiber reinforced polyamide Ultramid A3WG10 CR. The top mount with the polyurethane element and the polyamide housing is around 25 percent lighter than conventional aluminum die-cast versions with rubber.

Top mounts – the right material mix is decisive

The top mount links the shock absorber to the chassis and thus has a decisive influence on driving comfort and dynamics. The interplay between the materials of the individual components is therefore of crucial importance. Cellasto shows very good static and dynamic behavior, has a long life usage and takes up only a small amount of installation space. Components made of this material have been used in cars for more than 50 years.

50% glass fiber reinforced PA66 particularly suitable for dynamic loads

The PA66 grade Ultramid A3WG10 CR (CR=crash-resistant) is reinforced with 50 percent glass fibers and is therefore very rigid and solid, even at high temperatures. The engineering plastic is particularly suitable for dynamic loads and thus generally a good alternative to metal. Combined to form the top mount, the actual bearing, the jounce bumper and the dust tube for the shock absorber can be functionally integrated and achieve good damping and acoustics. With a manufacturing technique especially developed by BASF, housing and bearing are joined to each other permanently. The company’s CAE tool Ultrasim was used to calculate the load situations relevant for top mounts, the lifespan and the injection-molding process.