Thank you, Steven. I m Dave Ritchey and I m pleased to represent our DuPont Vespel high performance parts business in today s webinar.

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1 Turbochargers and Emissions Systems: Material Solutions to Help Downsize Engines DuPont Automotive Webcast hosted by SAE International Nov. 4, 2009 Dave Ritchey, Global Transportation Segment Leader, DuPont Kalrez Vespel business Volker Plehn, North American transportation development and sales leader, DuPont Kalrez Vespel business Thank you, Steven. I m Dave Ritchey and I m pleased to represent our DuPont Vespel high performance parts business in today s webinar. Over the past few years our teams have been applying fundamental materials science to some of the toughest fluid and motion control challenges including the challenges of moving parts in turbochargers and emission systems - parts with unique friction and wear requirements. Over the next few minutes I ll highlight some of the recent results we ve had in high temperature wear and friction testing. Then Volker Plehn, who has worked with many tier 1 and OEM s on new material applications, will cover several specific application successes coming from this work, with the hopes of generating some ideas where our science can help you. First, let me introduce what we mean by Science of Wear and Friction. (slide 2) In a webinar last year, you may have heard me discuss the gains we ve made in controlling FRICTION by focusing on the underlying science of friction. For example, shown here is a common plate on disc system with a lubricant in between the rotating surfaces. This system is commonly found in driveline applications like thrust washers and seal rings. By carefully optimizing material selection and design guidelines, while understanding the thermal needs of the system, we have been able to demonstrate 45 to 55% reduction in measured friction. A significant gain for rotating driveline components. More information on these Science of Friction results can be found at our website: tryvespel.dupont.com (slide 3) Today we d like to share similar step change improvements in WEAR solutions, which have come out of our Science of WEAR program. Wear can be modeled as shown here, by one object sliding against another. In this case a metal ball sliding against a polymer surface. While there are many types of wear, I ve simplified it to be the ability or Contact: Dial DuPont First

2 inability - of the substrate to resist fracturing as it attempts to resist the movement of the other object. Our scientists have been able to take a unique approach to modeling this wear especially wear at high temperatures. By defining a set of critical material properties that impact wear at high temperatures, we have been able to demonstrate improvements in wear in the range of 60-70%. Today, I ll be covering some of these advances, which can be applied directly to the world of turbochargers and emission controls. (slide 4) Let s looks at the critical environmental factors that influence the hot, dirty world of turbos & emissions. At top you ll see the basic needs long life and predictable operation. For long life you want little or no component wear. And for predictable response times you want friction to remain constant over the life of the vehicle pretty simple, right? Except now when we consider downsized turbocharged engines with advanced emission control systems we are finding the exposure conditions are pushing the performance limits of conventional materials. In both applications we are dealing with components moving at high speeds and operating adjacent to exhaust gases, which means application temperatures ranging from minus 40 to plus 300 C or even higher. In addition, there is typically contamination from carbon particles and highly acidic condensates. Due to the high temperatures involved, these are often non- lubricated applications, making lifetime design a critical and difficult performance requirement. Also we see the increasing use of aluminum which while it does reduce weight, it also adds new challenges for preventing wear and corrosion. Hopefully, this helps explain the connection between wear and friction in today s focus area of turbos and emissions. Now I d like to spend a few minutes on what we ve learned on high temperature wear. (slide 5) Here is some data generated during high temperature wear experiments. On the left is a typical compositional approach, where the composition of the material is varied, by say fillers or additives, and the wear performance is measured at elevated temperatures. Wear is plotted on the Y axis. Composition is plotted on the X axis. You can see the results in a scatter plot with little correlation. (slide 6) Contact: Dial DuPont First

3 Now using this same data, but calculating values for the materials property group results in a much different result. With the Materials Property Group (MPT) plotted on the x-axis, the wear results do show a good correlation. With this understanding we can start to define which fundamental material properties define wear at elevated temperatures, and then begin tailoring new compositions to specific end use requirements and new temperature capabilities let me give you an example. (slide 7) An early output of our Science of Wear program can be seen in our new Vespel SCP product family. When compared to standard PI, such as Vespel SP products, we can see a 60-70% reduction in wear, longer life at higher temperatures and higher Pressure times Velocity limits all while maintaining a coefficient of thermal expansion close to that of aluminum. All of these improvements are well suited for the environmental conditions found on the engine or near-exhaust gas systems. Now let s look closer at a few specific properties of Vespel SCP that are an important component in wear performance at high temperatures. (slide 8) On the left is young's modulus and flex modulus. The purple bar is one of the new SCP resins, the blue is conventional Vespel SP21. You can see that at 260C, the new product has a 2 to 3 times higher modulus than conventional polyimides. On the right is a measure of thermal stability a good indicator of component life at high temperatures - reported here as % weight loss at 370C after 100 hours. You can see a step change improvement in the ability of the SCP polymer, shown by the purple bar, to withstand the effects of prolonged exposure to high temperatures in this case exhibiting less than 2 % weight loss. This is nice laboratory work, which should predict improved performance in the real world. Now let s see if we get these same levels of improvement in actual application testing. (slide 9) Here is one example for EGR valves. Over the past few years several of our customers, have reported improvements in performance after evaluating Vespel SCP parts in emission valve applications which are exposed to high levels of soot and coke particles. Contact: Dial DuPont First

4 Not only does soot tend to adhere to conventional metal bushings and shafts, it also contributes to both wear problems and actuation speed problems primarily due to the change in friction properties over time. Here is a simple graph showing how one customer improved the life of an EGR valve with the use of Vespel SCP bushings. In this test, using a poorly tuned engine for maximum soot generation, conventional metal bushings would only last 1 or 2 test cycles. With the bushings replaced with Vespel SCP parts the valves continued to operate smoothly all the way to 7 cycles constituting 42 days of testing at which point the testing was stopped with the valves still operating within specification. Likewise as our parts are tested in emission applications, they have been exposed to a wide variety of chemical cocktails at elevated temperatures. Here I ve listed a few of the chemicals present in a typical diesel exhaust condensate used in successful customer evaluations. (slide 10) Now what about wear in dirty or contaminated environments? In several commercial applications, we have observed a unique property of Vespel that can give longer life to metal components. Here are microphotographs of contamination particles and how they interact with a wear surface. In the top photo, we can see how a contamination particle can affect an aluminum substrate during a wear test. Notice that the particle remains on top of the wear surface and results in groove formation and damage to the surface of the aluminum part. In the lower photo, under the same test conditions the contamination particle embeds into the Vespel part and remains below the wear surface. Notice the lack of groove formation we believe because the particle is no longer in the lubricant film and not able to cause additional damage to the wear surface. This happens to be another new product in our portfolio Vespel SP-2515 which was formulated specifically to improve friction, wear and sealing against aluminum components. Let s look again as to if this theoretical behavior can be demonstrated in actual end use conditions. (slide 11) Here are test results in which our Japan colleagues established a steady state wear condition using clean oil and three different resin compositions. While the test was running, they introduced contamination particles shown in the photograph. Contact: Dial DuPont First

5 The solid gray bars show the steady state wear rate with clean oil. The patterned bars show the wear rates after the contamination particles were added. Vespel demonstrates a 65% improvement in wear vs PEEK. We believe this is due to the ability of Vespel to allow particles to embed and not to cause additional damage. And now I ll turn it over to Volker to describe how these advances in material properties have been successfully applied to turbocharger and emission control devices. (slide 12) Thank you Dave. First I ll start with the world of turbochargers. While our application experience started in Europe many years ago, we have recently seen design responsibility being transitioned to both Asia and the Americas as each region needs to localize turbocharger technology for regional demands. As Dave discussed, our customers have confirmed Vespel can survive harsh, acidic condensates at elevated temperatures, as well as maintain its wear and friction properties even in the presence of soot or contamination even with little or no lubrication over the life of the engine. Here are application examples where Vespel has shown consistent, predictable friction and wear in demanding turbo applications. Vespel has been successfully tested in applications such as control arm ends and linkage bushings which are external to the turbocharger and exposed to the engine compartment environment. Engineers are also considering internal bearing components such as ball bearing retainers, shaft spacers and seals. (slide 13) In this slide are application examples of Vespel parts being used successfully in EGR applications again in similar harsh conditions. We see customers taking the historical learnings from diesel EGR systems and applying them to gasoline and multiple stage emission systems in all regions. With the increased use of electronic controls, these components must operate at very fast actuating speeds and we have demonstrated, even after millions of cycles, that Vespel parts retain their smooth consistent operation. As shown in the photos, Vespel has been successfully used in both internal bushings and external linkage systems. These examples are from Taiho and Wahler, both earlier adaptors of new technology. Contact: Dial DuPont First

6 While our team has successfully improved our offerings for friction and wear we are not finished. Let s look toward the future and see where Science of Wear and Friction could be applied next. (slide 14) Here is a table of the market forces we see continuing to drive new wear & friction solutions over the next 5 years. As other speakers discussed, the majority of new vehicles will move to downsized engines with turbochargers. Many of these will also use direct inject technology which moves gasoline engines very close to the performance and technology of diesel engines which will increase not only the pressures components are seeing but also will increase sliding velocities. And as we ve learned from Europe, controlling the emissions in direct inject engines like NOX and particulates will be a challenge, increasing the need for advanced emission control systems linked to turbo chargers. Not only must the new components operate in dirty hot environments, they must provide consistent friction performance; predictable response times ; and set new levels of reliability and component life. Which for DuPont Vespel, matches nicely with our Science of Wear and Friction fundamentals in which optimization of material properties, careful part design and a clear understanding of the thermal inputs are used to define the application requirements. (slide 15) So in closing, today you ve seen a few examples of how material science, along with the early involvement of our scientists and engineers, have resulted in the performance capability of turbochargers and emission components being pushed to new heights. Please give Dave or me a call or visit our web site, tryvespel.dupont.com if you desire additional information or have any questions. # # # The DuPont Oval Logo, DuPont and Vespel are registered trademarks or trademarks of DuPont or its affiliates. Contact: Dial DuPont First