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Currently, advancements in Rapid Prototyping (RP) technologies have led to considerable amount of research activities and has been playing a major role in the area of tooling development for which Rapid Tooling (RT) term was coined. While rapid prototyping techniques are employed to make prototype tools, the basic idea of the rapid tooling is to produce prototype and zero series parts by using prototype tools so the parts truly represent the future production. This paper will present an evaluation of a RP and RT technique in developing tools (punch and dies) for sheet metal forming, which had been manufactured and tested. Both punch and die have been manufactured by combining Stereolithography (SL), RP technique, with nickel electroforming process. The stereolithography technique that had been utilized in developing models for the tools had been built with modeling pattern called Accurate Clear Epoxy Solid (ACES).

There is a definite trend toward the increasing use of “Glass Encapsulation Technology” in the automotive industry. In this technology a glass object such as a window is placed within a mould and an elastomer is injected around the window giving a tight sealing system. A wide variety of materials are currently used as the sealing materials in either static or semi-static encapsulated glazing systems, including a wide range of “elastomers”. New thermoplastic elastomer compounds are being developed that are characterized by their consistent properties; including high melt-fluidity, very good surface appearance, sealing properties, and resistance to weathering. Compound performance is highly dependent on formulation variables as well as the chemistries of the base materials. KRATON® SEBS polymers1 are block copolymers of styrene and ethylene/butylene.

It has been long established fact that fuel economy is a key driving force of low viscosity gasoline engine oil research and development considered by the original equipment manufacturers (OEMs) and lubricant companies. The development of low viscosity gasoline engine oils should not only focus on fuel economy improvement, but also on the low speed pre-ignition (LSPI) prevention property. In previous LSPI prevention literatures, the necessity of applying Ca/Mg-based detergents system in the engine oil formulations was proposed. In this paper, we adopted a specific Group III base oil containing Ca-salicylate detergent, borated dispersant, Mo-DTC in the formulation and investigated the various effects of Mg-salicylate and Mg-sulfonate on the performance of engine oil. It was found that Mg-sulfonate showed a significant detrimental impact on silicone rubber compatibility while the influence from Mg-salicylate remains acceptable.

The increased use of recycled resins can create a dilemma for automotive designers. On the one hand, there is a growing initiative to increase recycled materials content on vehicles, globally. On the other hand, traditional methods of recycling polymeric materials -both thermoplastics and thermosets - can lead to degradation of engineering, mechanical, processing, and / or aesthetic properties of the resin. In an era where quality rules, this situation forces designers to accept a much lower percentage of recyclate than they might otherwise wish to use or risk unacceptable property loss in molded parts - something no automaker can “afford ” for long. Hence, a valuable feedstream of materials (polymers) often ends up destined for a landfill once many consumer products are broken down and more easily reusable or recyclable materials are salvaged. As a case in point, each passenger car built globally contains an average of 15 - 20 kg of nylon polymers.

Flexibility, oil resistance, and the need for heat resistance to 150°C-plus temperatures have traditionally limited automotive design engineers to two options - thermoset rubber or heat-shielding conventional thermoplastic elastomers (TPE). Both of these options present limitations in part design, the ability to consolidate the number of components in a part of assembly, and on total cost. This paper presents a class of high-performance, flexible thermoplastic elastomers based on dynamically vulcanized polyacrylate (ACM) elastomer dispersed in a continuous matrix of polyamide (PA) thermoplastic. These materials are capable of sustained heat resistance to 150°C and short-term heat resistance to 175°C, without requiring heat shielding. Recent advancements in blow molding and functional testing of the PA//ACM TPEs for automotive air management (ducts) and underhood sealing applications will be shown.

Weight and performance characteristics of the 1979 Pontiac Firebird soft bumper system are compared to those for a typical new (1979) metal/hydraulic design to evaluate the effects of the new standard. This study demonstrates the changing competitive environment in the automotive bumper market due to the introduction of the Part 581 Standard. The deep soft bumper concept is also discussed including its potential for achieving weight reductions in future elastomeric bumper systems.

A test program was conducted to characterize the impact response of an experimental 2-ply windshield construction with a polyurethane (PUR) plastic inner layer. Windshield impact tests were conducted using a linear impactor test facility. Principle among the findings was that the impact response of prototype PUR 2-ply windshields does not differ that significantly from that of baseline 3-ply HPR (High Penetration Resistance) windshields for the subcompact vehicle geometry tested. However, the impact responses of both PUR 2-ply and 3-ply HPR subcompact vehicle windshields were found to be highly variable. Average performance of either construction could thus be enhanced if ways could be found (and then implemented) to reduce this variability.

A test program was conducted to characterize the impact response of an experimental 2-ply windshield construction with a polyvinyl butyral / polyester (PVB/PET) inner plastic laminate. Windshield impact tests were conducted using a linear impactor test facility. Principal among the findings was that the measured impact response of prototype PVB/PET 2-ply windshields was highly variable. Average performance of this construction could thus be improved if ways could be found (and then implemented) to reduce this variability.

The present study compares the NVH performance of three different materials used on cam covers in automobiles, Aluminum (Al), Magnesium (Mg) and Thermoplastic (TP). The cam cover design used for this comparison was the 2004 Nissan Maxima 3.5L production cam cover which is made of a thermoplastic (TP). The Al and Mg covers for this study were created by sandcast, due to time constraints, via laser scanning techniques using the 2004 Nissan Maxima 3.5L production thermoplastic cover design. Note that sand-cast covers generally provide a less quiet sound field than the standard casting method. The Nissan production cover comes with a production baffle made of a similar material as the cover. Testing was conducted with and without the production baffle for all covers. The study was conducted for the production boundary condition of a non-isolated cover and a Freudenberg-NOK (FNGP) partially isolated cover. Isolated bolt assemblies using elastomeric grommets were used to isolate the cover.

The 2013 SRT Viper Carbon Fiber X-Brace, styled by Chrysler's Product Design Office (PDO), is as much of a work of art as it is an engineered structural component. Presented in this paper is the design evolution, development and performance refinement of the composite X-Brace (shown in Figure 1). The single-piece, all Carbon Fiber Reinforced Plastic (CFRP) X-Brace, an important structural component of the body system, was developed from lightweight carbon fiber material to maximize weight reduction and meet performance targets. The development process was driven extensively by virtual engineering, which applied CAE analysis and results to drive the design and improve the design efficiency. Topology optimization and section optimization were used to generate the initial design's shape, form and profile, while respecting the package requirements of the engine compartment.

2k clearcoat is the progressive step that is keeping coatings for elastomeric fascia in pace with the current automobile design, performance, and durability demands. Initially, rigid 2k coatings were applied over plastic for low temperature cure. Over metal, 2k rigid clearcoat produced a dramatic improvement in appearance and durability. Flexibility is the key attribute that a 2k clearcoat engineered for use over fascias must posses. Utilizing the same basecoat and primer, 2k flexible clearcoats are being successfully applied to flexible fascia, generating excellent appearance and outstanding durability.

Challenges surrounding OEM′s go far beyond to manufacture and delivery high quality vehicles. A perfect design and performance in the lowest cost possible is extremely essential to delivery to the customer the best vehicles. In order to guarantee all these targets, a robust process must be set to developed and implemented. It is known all process limitations, which faces the emergent markets and the lack of infrastructure considering the developed countries. All this limitations can deeply affect the robustness of the process. Some innovative solutions are becoming common from the engineering development combined with the manufacturing team to work out these limitations and provide excellent process stability. In this present paper it will be discussed the Bi component structural adhesive (2K PU epoxy) utilization to establish the process in the assembly line, mainly in order to improve parts dimensionally.

The need for light-weighting of automotive structures has spurred on a tremendous amount of interest in and development of low cost carbon fiber composite materials and manufacturing. This presentation provides a description of the commercial carbon fiber concept compared to traditional aerospace and specialty carbon fiber products. A specific update is presented on the development and commercialization of new low cost carbon fiber based on lignin / PAN precursor technology. The second focus of the presentation is on carbon fiber composite manufacturing processes, including carbon SMC, RTM, prepregs, and thermoplastic processes. Advantages and disadvantages of these processes are discussed, especially related to low cost manufacturing. Presenter George Husman, Zoltek Companies Inc.

TERBAN® hydrogenated nitrile rubber (HNBR) is a specialty elastomer used in demanding engineering applications such as the automotive, heavy duty, and industrial markets. It has excellent combination of heat, oil and abrasion resistance in addition to its high mechanical strength, very good dynamic and sealing properties. This paper will present data on aging HNBR for five thousand hours in an aggressive and un-stabilized B30A biodiesel fuel blend (70% ULSD, 30% SME, and an aggressive additive package) and explore the effect of HNBR polymer properties and vulcanizate composition on the performance in such fuel blends.

The new small and lightweight 2-cylinder liquid-cooled OHC gasoline engines were developed. These new engines are featuring high output, low vibration and noise radiation and so able to improve the comfortableness and amenity of applied utility machines. In this paper, the features of the new engines and the process to realize development targets are introduced. The basic structure adopted on the new engines is a liquid-cooled, inline 2-cyilinder layout with 360-degree firing intervals, twin balancer shafts, and an overhead camshaft that is driven by a cogged belt. Also various parts made of aluminum alloy and plastics could make the engine lighter. By these measures, the new engines could satisfy their hardest development targets, and realize their easy installation, higher versatility, and have the excellent features such as compact size, lightweight, high output, low exhaust gas emission and low vibration and noise radiation.

This SAE Standard specifies the test methods, dimensions, and requirements for single core 60 V cables intended for use in road vehicle applications where the nominal system voltage ≤60 V DC (25 V AC). It also specifies additional test methods and/or requirements for 600 V cables intended for use in road vehicle applications where the nominal system voltage is >60 V DC (25 V AC) to ≤600 V DC (600 V AC). Where practical, this standard uses ISO 6722 for test methods, dimensions, and requirements. This standard covers ISO conductor sizes which usually differ from SAE conductor sizes. It also covers the individual cores in multicore cables. See ISO 6722 for “Temperature Class Ratings”.

This Standard specifies the test methods, dimensions, and requirements for single-core 60 V cables intended for use in road vehicle applications where the nominal system voltage ≤ 60 V DC (25 V AC). It also specifies additional test methods and/or requirements for 600 V cables intended for use in road vehicle applications where the nominal system voltage is > 60 V DC (25 V AC) to ≤ 600 V DC (600 V AC). Where practical, this standard uses ISO 6722 for test methods, dimensions, and requirements. This standard covers ISO conductor sizes which usually differ from SAE conductor sizes. It also covers the individual cores in multi-core cables. See ISO 6722 for “Temperature Class Ratings”.

The first part of this paper describes air and gasoline heat-aging tests on various type 66 nylon resins. The results are pertinent for evaluating the suitability of these nylons for automotive applications such as the emission control canister and the gasoline vapor-liquid separator. In addition, data are presented to demonstrate that road salt caused no deterioration on test bars made from various 66, 610, and copolymer nylon resins which are in contact with galvanized zinc sheets in an acid environment. The second part of this paper discusses a survey which was made of a variety of automotive parts made of 66 nylon and acetal homopolymer to determine their quality after extended service. Parts, including body, chassis, engine, and transmission components, were removed from high mileage cars. Parts were evaluated for changes in dimension and strength. Their general condition was found to be excellent.

For the launch of the 800 series ARG set out to maintain the paint on line process for plastic bumpers developed for Maestro and Montego, to achieve this, new and exciting problems had to be overcome. A vehicle weight of 1420kg for the highest derivative, a maximum centreline deflection of 15mm front and rear, a profile collapse calculated to absorb energy within 65% of it's cross sectional area and show no damage within the terms of the ECE 42 regulation, ie 4kph centreline and mounting, 2.5kph corner and a perfect colour match combined with the highest quality.

The paper investigates the interaction between soil and tractor tires through a 2D numerical model. The tire is schematized as a rigid ring presenting a series of rigid tread bars on the external circumference. The outer profile of the tire is divided into a series of elements, each one able to exchange a normal and a tangential contact force with the ground. A 2D soil model was developed to compute the forces at the ground-tire interface: the normal force is determined on the basis of the compression of the soil generated by the sinking of the tire. The soil is modeled through a layer of springs characterized by two different stiffness for the loading (lower stiffness) and unloading (higher stiffness) condition. This scheme allows to introduce a memory effect on the soil which results stiffer and keeps a residual sinking after the passage of the tire. The normal contact force determines the maximum value of tangential force provided before the soil fails.