Glass-Filled Nylon 6 and PBT in Two-Part Top Steering Wheel Column Module Housing.

The new BMW 3 to 7 series of vehicles with rear-wheel drive from the BMW Group features a nylon 6 and two PBT resins from BASF, Florham Park, N.J., in the top column module that connects the steering wheel with the control unit, making it about 20% lighter than the previous model. Outstanding surface finish, good UV resistance and excellent mechanical properties are also claimed.

French automotive supplier Valeo developed the new module, whose housing and levers are made of BASF’s Ultramid B3EGG10 SI (surface improved) resin—a 50% glass-filled nylon 6, originally developed for the furniture industry, Ultradur B4520 unreinforced PBT and Ultradur B 4300 G4, a 20% glass-filled PBT.

The indicator and windshield wiper levers are made of the surface highly-glass-filled nylon 6 grade, and noted for the particularly high-quality surface finish and stability of the material.

The two-part core module employs the two different PBT grades. The lower carrier housing is made of the 20% glass-filled PBT, which is processed by the German company Buck Spritzgussteile Formenbau using the MuCell process. It is said to result in a 10% weight reduction along with increased dimensional stability without any adverse effect on the high rigidity and excellent chemical resistance of the material. The upper top column module housing is made of the unreinforced PBT, noted for its reportedly low-water uptake and resultant high dimensional stability. Moreover, it combines an appealing surface finish with excellent dimensional stability at high temperatures---a combination of properties that is said to ensure that the steering wheel can be mounted safely on the top column module