Mark IV launches a new Air Intake Manifold answering to high level PSA Peugeot Citroën specifications thanks to Technyl Star™ polyamide unique properties

Orbey, France, October 20th, 2004 - Mark IV announces today the launch of a new Air Intake Manifold developed with the support of Rhodia Engineering Plastics to answer the highly demanding specifications of a new PSA Peugeot Citroën 2L 4-cylinder 16-valve gasoline engine. This engine - EW10A - will be installed first on the new Citroën C5.

The use of Technyl Star™, the very high flow polyamide of Rhodia Engineering Plastics, together with a close collaboration on parts development and validation between Mark IV and Rhodia teams, allowed Mark IV to answer all the stringent specifications of this application while benefiting of various process productivity advantages brought by

Technyl Star™.

The high requirements of the new Mark IV AIM, including limited size and weight, led to several technical challenges, as they needed to be fulfilled under critical conditions of use with a high level of consistence during the whole of the engines lifetime.

Regarding burst pressure, the part had to resist to both static pressure (5.5 bars relative during 5 minutes at room temperature and 3.5 bars relative at 110°C) and dynamic pressure – backfire ( increase of 7.5 bars relative in only few milliseconds ).

As far as NVH was concerned several requirements had to be fulfilled. The acoustic behavior specifications were defined on the complete engine. The AIM was designed to contribute to the limitation of the global noise level coming from the engine by minimizing the inside volume variation in use (so called volumic rigidity) to ensure a high acoustical performance of the part and, as a consequence, of the whole engine. In relation to the vibration behavior, critical specifications were mentioned concerning the part’s reaction when submitted to mechanical excitation coming from the engine through the AIM fixation points, to preserve electronic components fixed on the AIM. So, besides the resistance to vibrating endurance, a severe criteria indicated that the maximal local acceleration level had to be maintained under 245 m.s-2 (25g) in order to keep the 2.5 kg ETC - electronic throttle body operational.

Finally, the new Mark IV AIM had also to answer to PSA Peugeot Citroën’s highly demanding requirements in term of quality and durability : 240 000 km in standard conditions of use.

The close technical collaboration between the Mark IV and Rhodia Engineering Plastics teams has been key to respect the tight project schedule and stringent functional requirements, first in CAE conception but also in part validation.

CAE teams of both companies focused on part burst pressure resistance and vibration behavior, at a minimal weight and dimension, where material properties have a strong influence on results.

As Rhodia has built a unique material properties database recording all its Technyl® and Technyl Star™ grades, taking into account orthotropic behavior of glass fiber filled products, visco-elasticity and temperature dependency, ageing behavior, etc… a material was rapidly identified as the best solution to offer the right balance of properties to fulfill the requirements of the part : Technyl Star™ S 218 V35 bk31N, a 35% glass filled heat stabilized high fluidity polyamide.

The accuracy of the recorded properties led to a precise prediction of the static burst pressure resistance, while a specific backfire test done at the Rhodia Technical Automotive Centre in

Freiburg, Germany, with the use of high speed video cams, confirmed break location and values for the dynamic burst pressure.

Visco-elastic properties brought efficient solutions to the demanding vibration requirements, which have been then validated on the Mark IV shaker system.

Finally, the CAE allowed to optimize the injection gate number and predict precisely the clamping force needed.

Concerning validation, Mark IV and Rhodia Engineering Plastics’ laboratories shared resources and costs during the prototype and serial phase. Mark IV performed several successive dynamic pressure tests on the same part, which confirmed that the

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+33 4 72 89 29 24

jerome.pisani@​eu.rhodia.com

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