Automotive Material Prevents Interior Squeaking

Using the tailored Arpro as the sun visor’s core provides simpler moulded inserts, enhanced energy absorption, component consolidation, easier assembly, lighter weight and enhanced recyclability. JSP has developed an anti-squeak formulation of Arpro expanded polypropylene (EPP) for car interiors. JSP was approached by specialist moulder Febra to provide a solution to noise vibration and harshness (NVH) issues and was able to offer a variant with a nonslip additive that reduces noise.

Interior ‘squeaks’ are created when components adjacent to each other or to the body of the vehicle (such as a spare-wheel-insert toolbox) vibrate independently. The noise is the result of the “stick-slip” effect caused by the transfer of vehicle kinetic energy overcoming friction and creating movement between the parts. The new tailored Arpro formulation significantly reduces stick-slip, helping lower interior noise dramatically.

“Squeaks and rattles are not only an issue for the engineer, but also for the driver”, explains Paul Compton, JSP’s Executive Vice President and Chief Operating Officer (Europe). “Now that powertrain and road noise in the modern car are lower, vehicle interiors have become the focus for NVH reduction”.

“Squeaks also affect the perceived quality of a product and can become a warranty issue for the OEM”. Sun visors are a prime example of noise generation, where the interaction between multiple materials creates alternating sound frequencies, further increasing noise harshness. Using the tailored Arpro as the sun visor’s core provides simpler moulded inserts, enhanced energy absorption, component consolidation, easier assembly, lighter weight and enhanced recyclability.