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The continuous enhancement of safety requirements due to greater traffic density, higher speeds, and improved driver comfort has boosted worldwide the introduction of power brake actuators as a standard accessory in passenger cars. Historically the brake actuator control housing has been made from thermoset phenolic compounds due to this material's good dimensional stability. A special glass-reinforced thermoplastic PET compound has been developed and successfully used as alternative material for such control housings. Compared to phenolic it offers the required improved design freedom, lighter weight, better heat aging and improved fatigue behavior, along with similar system costs. This material is widely used by European brake suppliers and vehicle producers and is starting to be used in both North America and Japan.

Continued development in the area of polymer chemistry, alloying and compounding and growing understanding of engineering principles as applied to thermoplastic materials has allowed considerable expansion of the applications for thermoplastics in areas formerly not considered for these materials. The development of a thermoplastic roller valve lifter guide described in this paper illustrates some of the principles and techniques which can be used to develop aggressively innovative applications for thermoplastic materials and emphasizes the advantages to be gained by applying simultaneous engineering principles in such developments.

Styrene Maleic Anhydride (SMA), typically glass reinforced, is widely used in automotive for interior trim and instrument panels. However presently available materials are not able to fill all of the increasing demands for both toughness and temperature resistance that are being required by automotive OEM's due to higher quality requirements, passive restraint legislation, and increased global competition. This paper will review a new family of SMA's that, due to differences in the manufacturing process and formulation, are available with a wider window of available temperature resistance and toughness properties. The properties of these materials will be reviewed along with comparisons to other materials such as existing SMA's, polycarbonates, modified poly phenylene oxides/ethers, ABS and other commonly used plastics for interior trim applications. Interior applications, along with their requirements, where these materials have found use will also be reviewed.

This paper will review materials used for bearing and wear applications, test methods used to characterize materials, wear, friction and pressure - velocity (PV) data at both ambient and elevated temperatures along with applications for these materials. Much of these data, particularly at elevated temperatures, has recently been generated using specialized equipment designed for this purpose. Materials reviewed will include acetal and nylon for low load bearing applications, molybdenum disulphide and PTFE modified materials for medium loads and newer higher temperature materials for higher loads and temperatures such as 46 Nylon, Polyamide-imide (PAI) and PEEK.

Nylon 46 is a new material with a wide variety of engine applications… Compared to traditional materials such as 66 nylon, it offers improved temperature resistance, toughness, fatigue resistance, bearing properties, and creep. Application areas include timing chain tensioners, bearing cages, transmission components, sensors, and valve covers.