Gear Technology Magazine

New Sulfide Material from Ticona Makes Braking Easier

January 4, 2005
Fortron linear polyphenylene sulfide (PPS) for actuator housings and gears to help transfer power from the actuator motor to the brakes. Forton PPS,manufactured by Ticona, has worked in actuators of rear wheels, like those found in Volkswagen, Bentley, Bugatti and Lancia automobiles, because of the material’s dimensional stability across a wide temperature range as well as impact resistance, chemical resistance and processability. According to the company’s press release, each PPS actuator is comprised of an injection molded body and cover. The two components are ultrasonically welded to create the final assembly. The PPS spur gear within the actuator has a diameter of about 30 mm and is driven by a belt from an electric motor. The gear then drives a transmission that actuates the brake. The key requirement that led to the selection of Fortron PPS in the actuator is its ability to remain dimensionally stable at temperatures from well below 0ー to 180ーC. It also can withstand the impact of stones thrown up by tires from the road surface and has excellent resistance to brake fluid and other automotive chemicals. The PPS also flows in molding to create low flash parts, eliminating the need for secondary finishing steps for the gears.