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Basic automotive steering wheel armature design has been largely unchanged for years. A cast aluminum or magnesium armature is typically used to provide stiffness and strength with an overmolded polyurethane giving shape and occupant protection. A prototype steering wheel armature made from a unique recyclable thermoplastic eliminates the casting while meeting the same stiffness, impact, and performance criteria needed for the automotive market. It also opens new avenues for styling differentiation and flexibility. Prototype parts, manufacturing, and testing results will be covered.

The automotive industry continues to strive for mold-in-color (MIC) solutions that can provide metallic flake appearances. These MIC solutions can offer a substantial cost out opportunity while retaining a balance of weathering performance and physical properties. This paper discusses a predictive engineering package used to hide, minimize and eliminate flow lines. Material requirements and the methods used to evaluate flowline reduction and placement for visual inspection criteria are detailed. The Nissan Quest® luggage-rack covers are used to illustrate this application. The paper also explores how evolving predictive packages offer expanding possibilities.

OEM and Tier One integrated suppliers are in constant search of cockpit system components that reduce the overall number of breaks across smooth surfaces. Traditionally, soft instrument panels with seamless airbag systems have required a separate airbag door and a tether or steel hinge mechanism to secure the door during a deployment. In addition, a scoring operation is necessary to ensure predictable, repeatable deployment characteristics. The purpose of this paper is to demonstrate the development and performance of a cost-effective soft instrument panel with a seamless airbag door that results in a reduced number of parts and a highly efficient manufacturing process. Because of the unique characteristics of this material, a cost-effective, lightweight solution to meet both styling requirements, as well as safety and performance criteria, can be attained.

To determine what effect (measured in haze), UV exposure has on polycarbonate inner lenses (coated and uncoated), when positioned behind qualifying (UV absorbent) and non-qualifying (UV transmitting) outer lens materials (clear and red). Plastic inner lenses are those covered by another material and are not exposed directly to sunlight.

This paper describes a bumper system designed to meet the current FMVSS (Federal Motor Vehicle Safety Standard) and ECE42 legislation as well as the European Enhanced Vehicle Safety Committee (EEVC) requirements for lower leg pedestrian impact protection [1] (The EEVC was founded in 1970 in response to the US Department of Transportation's initiative for an international program on Experimental Safety Vehicles. The EEVC steering committee, consisting of representatives from several European Nations, initiates research work in a number of automotive working areas. These research tasks are carried out by a number of specialist Working Groups who operate for over a period of several years giving advice to the Steering Committee who then, in collaboration with other governmental bodies, recommends future courses of action designed to lead to improved safety in vehicles).

The aesthetic requirements for rear combination lamps have risen due to the increased use of optic free lens. The objective of this study was to develop a methodology to characterize the relative aesthetic performance for thermoplastic resins utilized for rear combination lamp housings. This study focuses upon the use of a direct metallization process. The results of this study will allow project engineers to better understand the relative performance of various materials.

Automobile headlamps are highly controlled products that must meet various performance standards to be commercialized. The combination of the bulb and lens must emit acceptable color and light output. Commercially available headlamps use different types of bulbs but usually a clear or slightly tinted lens. In the past few years, high performance bulbs have been used. These are known as HID or xenon lamps and are characterized by their bluer color compared to standard halogen bulbs. This paper explores some of the possibilities that new lens material can offer in terms of design and aesthetics with little or no impact on lighting performance as tested per the Society of Automotive Engineers (SAE) J1383 [1]. Light stability of these new lens materials is also discussed.

A model has been developed and implemented at GE Plastics that predicts a material's color shift when weathered. The material's color shift is due to the summation of color shifts from each individual component. By individually measuring the change in each component's optical coefficients upon weathering and using a multiple light scattering model, one can predict the color shift of a material composed of mixtures of these components. The model has been shown to have a standard deviation of 0.4 to 0.9 when predicting color shifts E*, for PC-polyester copolymers, ABS, and ABS/PC blends using an automotive exterior test, SAE J1885, ASTM D 4674, and ASTM D 4459.

Current accelerated weathering protocols such as SAE J1960 or ASTM G26 do not provide reliable, predictive results for engineering thermoplastics. Correlation factors among resin types and even different colors of a single resin have variations that are 60-100% of the mean at the 95% confidence level, making these tests useless for lifetime prediction or even reliable ranking of materials. We have developed improved conditions using CIRA/sodalime-filtered xenon arc, a more rain-like water spray, and occasional sponge-wiping of the samples. The data for gloss loss and color shift agree very well with Florida data giving a correlation factor of 3100±680 kJ/m2 (at 340 nm) per Florida year at the 95% confidence level. The acceleration factor is 7.6x.

This paper describes a bumper system design that satisfies both current FMVSS legislation as well as the European Enhanced Vehicle Safety Committee (EEVC) requirements for lower leg pedestrian impact protection. The dual performance solution is achieved through a combination of material properties and design. Using Computer Aided Engineering (CAE) modeling, the performance of an injection molded energy absorber (EA) was analyzed for pedestrian protection requirements of knee bending angle, knee shear displacement, and tibia acceleration, 4Kph pendulum and barrier impacts (ECE42, FMVSS), and 8Kph pendulum and barrier impacts (CMVSS, FMVSS). The results demonstrate how an injection molded EA using polycarbonate/polybutyelene terephthalate (PC/PBT) resin (Figure 1) can meet both FMVSS and pedestrian safety requirements and can do so within a packaging space typical of today's vehicle styling.

This paper will discuss, compare, and contrast current materials, designs, and manufacturing options for fuel filler doors. Also, it will explore the advantages of using conductive thermoplastic substrates over other materials that are commonly used in the fuel filler door market today. At the outset, the paper will discuss the differences between traditional steel fuel filler doors, which use an on-line painting process, and fuel filler doors that use a conductive thermoplastic substrate and require an in-line or off-line painting process. After reviewing the process, this paper will discuss material options and current technology. Here, we will highlight key drivers to thermoplastics acceptance, and look at the cost saving opportunities presented by the inline paint process option using a conductive thermoplastic resin, as well as benefits gained in quality control, component storage and coordination.

There are a multitude of opportunities to utilize two-shot or overmolding technology in the automotive industry. Two-shot or overmolding a thermoplastic elastomer onto a rigid substrate can produce visually appealing, high quality parts. In addition, use of this technology can offer the molder significant reductions in labor and floor space consumption as well as a reduction in system cost. Traditionally, two-shot applications were limited to olefinbased TPE's and substrates, which often restricted rigidity, structure and gloss levels. With the development of thermoplastic elastomers that bond to engineering thermoplastics, two-shot molding can now produce parts that require higher heat, higher gloss and greater structural rigidity. This paper will outline engineering thermoplastics that bond with these new elastomers, discuss potential applications, and review circumstances that offer the best opportunity to call upon the advantages of two-shot and overmolding technology.

An efficient energy absorber (EA) will absorb impact energy through a combination of elastic and plastic deformation. However, the EA is typically coupled with a steel reinforcing beam, which can also elastically and plastically deform during an impact event. In order to design and optimize an EA/Beam system that will meet the specified vehicle impact requirements, the response of the entire assembly must be accurately predicted. This paper will describe a finite element procedure and material model that can be used to predict the impact response of a bumper system composed of an injection molded thermoplastic energy absorber attached to a steel beam. The first step in the process was to identify the critical material, geometric, and boundary condition parameters involved in the EA and Beam individually. Next, the two models were combined to create the system model. Actual test results for 8km/hr.

The history behind Polymer Class “A” Body Panels for automotive applications is very interesting. The driving factors behind these applications have not changed significantly over the past sixty years. Foremost among these factors is the need for corrosion and dent resistance. Beginning with Saturn in 1990, interest in polymer body panels grew and continues to grow up to the present day, with every new global application. Today, consumers and economic factors drive the industry trend towards plastic body panels. These include increased customization and fuel economy on the consumer side. Economic factors such as lower unit build quantities, reduced vehicle mass, investment cost, and tooling lead times influence material choice for industry. The highest possible performance, and fuel economy, at the lowest price have always been a goal.

This paper will describe an approach to satisfying proposed European Enhanced Vehicle Safety Committee (EEVC) legislation for lower leg pedestrian impact. The solution for lower leg protection is achieved through a combination of material properties and design. Using Computer Aided Engineering (CAE) modeling, the performance of an energy absorber (EA) concept was analyzed for knee bending angle, knee shear displacement, and tibia acceleration. The modeling approach presented here includes a sensitivity analysis to first identify key material and geometric parameters, followed by an optimization process to create a functional design. Results demonstrate how an EA system designed with a polycarbonate/polybutyelene terephthalate (PC/PBT) resin blend, as illustrated in Figure 1, can meet proposed pedestrian safety requirements.

Automotive interiors are undergoing rapid transformation with the introduction of invisible PSIR integral systems. This styling trend requires continuous class A surface for the Instrument Panel (IP) and introduces complexities in the design and analysis of PSIR integral systems. The most important criterion for airbag doors is that it must open as intended, at the tearseam, within the deployment temperature range and without fragmentation. Consequently it is imperative that in analytical simulations, the finite element model of the tearseam is accurate. The accuracy of the model is governed by (a) optimal level of refinement, (b) surface geometry representation and (c) material model. This paper discusses modeling methodology for tearseams with respect to mesh refinement and the effect of geometry.

The evolution toward the use of electrostatic painting processes has been driven primarily by environmental legislation and efforts to improve efficiencies in the painting process. The development of conductive substrate material compliments the industry trend toward a green environment through further reductions in emissions of volatile organic compounds during the painting process. Traditionally, electrostatic painting of thermoplastics requires that a conductive primer be applied to the substrate prior to topcoat application. The conductive polymer blend of polyphenylene ether and polyamide provides sufficient conductivity to eliminate usage of conductive primers. Additional benefits include improved transfer efficiencies of the primer and top coat systems, uniform film builds across the part, and improved painting of complex geometries.

Automotive exterior paint systems can significantly affect the impact performance of thermoplastic body panels. To utilize the benefits of predictive engineering as a tool to assist in the design and development of thermoplastic body panels, thermoplastic body panel materials have been characterized with typical automotive paint systems for use for finite element modeling and analysis. Paint systems used for exterior body panels can vary from rigid to more flexible, depending on the vehicle manufacturer's specifications. Likewise, thermoplastics for body panels vary in mechanical properties, primarily depending on the heat performance requirements of the application. To understand the effects of paint systems on impact performance of thermoplastic body panels, two different paint systems, representing “rigid” and “more flexible,” were evaluated on two body panel grades of thermoplastics with different mechanical properties.

The drive to reduce weight, simplify assembly, and cut total system cost in today's vehicles is relentless. Replacing metal systems with thermoplastics has been of considerable interest in the engineering community. The current generations of engineering thermoplastic resins are enabling the use of plastic systems in demanding underhood applications. Technical data and discussion regarding the materials, design, molding, and assembly of lightweight composite throttle bodies will be presented in this paper. Comparisons with machined aluminum throttle housings are drawn to establish a baseline with the throttle body housing component that is most common in production today. Design flexibility and process simplification are some of the approaches highlighted. Much of the technical information provided in the paper applies to both cable driven mechanical throttle bodies as well as electronic throttle bodies under development.

As the global auto industry wrote the final chapter on its first century, we saw the average thickness of an automotive instrument panel drop from 3.0 mm-3.5 mm to 2.0 mm-2.3 mm, as found in the 1999 Volkswagen Jetta and Golf. By reducing the wall thickness of the instrument panel, Volkswagen started an industry trend: both OEMs and tiers are investigating technologies to produce parts that combine a lower cost-per-part via material optimization and cycle-time reduction with the superior performance of engineering thermoplastics. The goal is to produce parts that are positioned more competitively at every stage of the development cycle - from design, to manufacturing, to assembly, to “curb appeal” on the showroom floor. The key to this manufacturing and design “sweet spot” is a technology called thinwall - the molding of plastic parts from engineering thermoplastics with wall thicknesses thinner than conventional parts of similar geometry.