Groupe PSA

In the automotive sector, noise performance is among the essential data that must be considered from the design stage of new models with the aim being to minimise squeaking and grinding in order to make the car interior as noise-free as possible. With this in mind, the tribology experts of the Groupe PSA entered into partnership agreements with Cetim’s experts to work together on reducing the noise inside cars. “This new study conducted with Cetim was intended to get better knowledge of the materials that we use as regards noise performance and obtain a method to assess this performance from the design stage of the vehicles”,confirmed Pierre Charles, tribology specialist at PSA.

A hundred tests

The study was first initiated on parts entering into contact in the control systems and the went on to cover 25 pairs of polymer / polymer and polymer / steel materials. Approximately one hundred tests were performed. “Two years of studies were required to understand the noise excitation mechanisms, develop software applications capable of predicting them, propose formulations to reduce the noise performance potential and above all develop a testing procedure which can be applied to all new materials that we are likely to use in our vehicles”, added Dominique Pierrat, plastic processing specialist at PSA. 

Contribution of digital technology

As part of this work, a digital approach served to demonstrate that it was possible to reproduce the complex phenomena noted during the tests: stick-slip, sprag-slip, etc. “Nevertheless, tribology is an especially complex field were many variables can come into play. As a result, at present, we are continuing to further optimise the developed method”, continued Dominique Pierrat.