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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.

As part of the 1997 Propane Vehicle Challenge, a team of twelve UTEP students converted a 1996 Dodge Grand Caravan with a 3.3 L V6 engine to dedicated Liquefied Petroleum Gas (LPG) operation according to the 1997 Propane Vehicle Challenge (PVC) competition rules (16). The 1997 UTEP team developed an LPG liquid phase port fuel injection (LPP-FI) system for the minivan. The UTEP design strategy combines simplicity and sound engineering practices with the effective use of heat resistant materials to maintain the LPG in the liquid phase at temperatures encountered in the fuel delivery system. The team identified two options for fuel storage with in-tank fuel pumps. The competition vehicle incorporates a five-manifold eight inch diameter Sleegers Engineering LPG tank fitted with a Walbro LPTS in-tank pump system, providing a calculated range of 310 city miles and 438 highway miles.

THE development of the two-stage torque converter with automatic double clutch is presented here. The author covers particularly the substitution of casting for fabrication for several of the units in the transmission.

In October 1999, General Motors contracted Dana Corporation to manufacture an all-aluminum spaceframe for the 2006 Chevrolet Corvette Z06. Corvette introduced its first ever all-aluminum frame (see Figure 1) to the world at the 2005 North American International Auto Show (NAIAS) in Detroit, Michigan. The creation of this spaceframe resulted in a significant mass reduction and was a key enabler for the program to achieve the vehicle level performance results required for a Z06 in an ever-growing market. Dana Corporation leveraged ALCOA's (Aluminum Company of America) proven design capabilities while incorporating new MIG welding, laser welding, Self-Pierce Riveting (SPR), and full spaceframe machining to join General Motors (GM) Metal Fabrication Division's (MFD) hydroformed rails to produce the Corvette Z06's yearly requirement of 7000 units. This paper describes the technologies utilized throughout the assembly line and their effect on the end product.

In order to take full advantage of SiC, a high temperature package for power module using SiC devices was designed, developed, fabricated and tested. The details of the material selection and fabrication process are described. High temperature reliability test and power test shows that the package presented in this paper can perform well at the high junction temperature.

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.

During sheet metal forming processes, the friction conditions have a decisive influence on forming limits, the robustness of the production process and the quality of the parts produced, with significant forces required to overcome friction between the sheet and the tools. If lot-to-lot reproducibility is to be guaranteed, an appropriate method of characterizing the sheet surface topography is needed to monitor the sheet metal fabrication process. Newly developed optical measurement techniques and computer workstation technology are presented which enable the topography of sheet surfaces to be described in three dimensions.

To meet the demands of continually increasing energy requirements, the off-shore operations to explore and recover petroleum deposits from beneath the ocean bottom are taking place under increasingly difficult environmental conditions. This has led to the development of types of equipment well beyond the possibilities or the imaginable future requirements of twenty years ago. When conditions require the fabrication of off-shore platforms on land, to be floated to the erection site, lifted and placed as a single unit of up to 3000 tons, revolving cranes capable of performing such lifts become a necessary part of that development.

This paper discusses work performed in research, design, and development of sensors for measurement of local dynamic surface temperatures on re-entry vehicles. Included are discussions of the basic requirements and related system design factors, the transducer concepts and sensor assembly configurations considered, and the materials investigations and engineering tests conducted. Design requirements are presented for the twin-lead thermocouple probe temperature sensor chosen as the most feasible concept for early implementation. The most promising thermocouple materials and fabrication processes are defined and the additional precision testing and development requirements for final design are outlined. Information not previously reported in available literature includes preliminary data from tests up to4300°F showing (1) excellent oxidation resistance of Iridium, and (2) oxidation protection of thermocouple elements in “gas tight” sheaths of thoria and zirconia.

Engines are assigned big subjects such as low emission and low fuel consumption as well as higher output (higher efficiency) in the latest trend of environmental protection. In order to meet these requirements, Air/Fuel ratio of recent high performance engines is being arranged leaner than that of conventional engines. As a result exhaust valve seat inserts used in these engines have problems of their wear resistance because of high exhaust gas temperature. By analyzing wear mechanism under the lean burn conditions, authors developed material for exhaust valve seat inserts which show superior wear resistance under high operating temperature. For the purpose to enhance heat resistance, authors added alloy steel powder for matrix powder and used hard particles which have good diffusion with matrix. The developed material does not include Ni and Co powders for cost saving and has superior machinability.

Vertical-Junction-Field-Effect-Transistors (VJFETs) are currently the most mature SiC devices for high power/temperature switching. High-voltage VJFETs are typically designed normally-on to ensure voltage control operation at high current-gain. However, to exploit the high voltage/temperature capabilities of VJFETs in a normally-off high-current voltage-controlled switch, high-voltage normally-on and low-voltage normally-off VJFETs were connected in the cascode configuration. In this paper, we review the high temperature DC characteristics of VJFETs and 1200 V normally-off cascode switches. The measured parameter shifts in the 25°C to 300°C temperature range are in excellent agreement with theory, confirming fabrication of robust SiC VJFETs and cascode switches.

Fabrication and assembly of the majority of control surfaces for Boeing’s 777X airplane is completed at the Boeing Defense, Space and Security (BDS) site in St. Louis, Missouri. The former 777 airplane has been revamped to compete with affordability goals and contentious markets requiring cost-effective production technologies with high maturity and reliability. With tens of thousands of fasteners per shipset, the tasks of drilling, countersinking, hole inspection, and temporary fastener installation are automated. Additionally and wherever possible, blueprint fasteners are automatically installed. Initial production is supported by four (4) Electroimpact robotic systems embedded into a pulse-line production system requiring strategic processing and safeguarding solutions to manage several key layout, build and product flow constraints.

Multiple automotive systems are now being developed which require an imager or vision chip to provide information regarding vehicle surroundings, vehicle performance, and vehicle passenger compartment status. Applications include lane departure, lane tracking, collision avoidance, as well as occupant position, impaired driver, and occupant identification. These applications share many requirements, including robust design, tolerance for the automotive environment, built in self-test, wide dynamic range, and low cost. In addition, each application has unique requirements for resolution, sensitivity, imager aspect ratio, and output format. In many cases, output will go directly to vehicle systems for processing, without ever being displayed to the driver. Commercial imager chips do not address this wide spectrum of requirements. A CMOS imager chip has been designed to address these unique automotive requirements.

Fundamental differences exist between sheet metal forming and hydroforming processes. Sheet metal forming is basically a one step metal fabrication process. Almost all plastic deformation of an originally flat blank is introduced when the punch is moved normal to a clamped sheet metal. Hydroforming, however, consists of multiple steps of tube making, pre-bending, crushing, pressurization, etc. Each of the above mentioned steps can introduce permanent plastic deformations. The forming limit diagram obtained for sheet metal forming may or may not be used in hydroforming evaluations. A failure criterion is proposed for predicting bursting failures in tube hydroforming. The tube material's stress-strain curve, obtainable from uniaxial tensile test and subjected to some postulations under large stress/strain states, is used in judging the failure.

A catalyzed hydrocarbon (HC) trap aiming at the super-ultra low emission vehicle (SULEV) regulation was developed using a metal-impregnated zeolite. To enhance the adsorption and to raise the desorption temperature for a wide range of HC species, the modification of zeolite with certain metals was needed and Ag was found to be the most promising. Using a Ag impregnated zeolite, a three way catalyst was prepared, and its HC purification ability for a model gas simulating cold-start HCs was studied. Its heat resistance was also examined. A vehicle test for a fresh catalyzed HC trap showed that the cold-start HC after the newly developed trap almost reached the SULEV regulation level.

DASH 47R is a cementitious composite initially formulated for use as an autoclave molding/tooling material. A unique matrix and aggregate system imparts unusually high strength and excellent vacuum integrity to DASH 47 at moderately high temperatures even though DASH 47 molds are cast at ambient temperature over commonly used pattern materials. This paper reviews the formulation and properties of DASH 47, and outlines its fabrication method and curing schedule for thin-shelled autoclave tools. In addition, examples of other molding applications for DASH 47 are shown in this paper.

Automotive friction materials are composites containing three kinds of components: an organic binder, fiber for reinforcement, and property modifiers. At low braking temperatures, the wear rate of the friction materials is controlled primarily by abrasive and adhesive mechanisms. At higher braking temperatures, the wear rate increases exponentially with increasing temperature due to thermal degradation of the binder and other components, and the exponential wear rate is frequently accompanied by brake fade. Thus, one method of reducing thermal wear and fade tendency is to lower the temperature at the rotor/friction material interface. Since the rate of heat transfer from the interface is mostly dependent upon the conductive and convective modes, a rotor of high thermal conductivity will have a significant advantage over a rotor of low conductivity, if the heat capacity remains the same.

The Model-Based Development (MBD) paradigm is widely used for embedded controls development, with the MathWorks Simulink modelling environment being extensively used in the automotive industry. As production-scale Simulink models are typically large and complex, there exists a need to decompose them properly in order to facilitate their maintainability, understandability, and evolution. MathWorks recommends the use of three constructs for model “componentization” or decomposition: the Subsystem, Library, and Model Reference. However, a recently added construct introduced in Simulink R2014b, the Simulink Function, can also be used for this purpose, while also supporting information hiding due to the construct’s ability to be scoped and encapsulate data.

Nickel-5 Aluminum (95 % Nickel-5 % Aluminum) is widely used in the aircraft engine industry. The excellent adhesive and cohesive strength of the coating, oxidation resistance and machinability make it an ideal material as both a bond coat for subsequent topcoats and as a build up material for dimensional restoration of worn or mismachined components. Plasma spraying has traditionally been the thermal spray process used to apply nickel aluminum, and the technical properties and performance characteristics are well documented. More recently, wire arc sprayed nickel aluminum is becoming widely used as an alternative to plasma spraying due to higher bond strengths, reproducibility, better machinability and more favorable economics. This paper presents the results of a testing program designed to compare the technical properties of arc sprayed versus plasma sprayed Nickel-5 Aluminum coatings.

The vast majority of products contain joints, therefore, joining technology is key to the strategic implementation of new materials. This paper considers three innovative solutions to industrial problems ClearWeld™ A recently developed technique for laser welding materials, creating a joint almost invisible to the human eye. AdhFAST™ This novel, three-in-one fastener, allows adhesive to be injected through the middle of the device whilst retaining the joint and controlling bondline thickness Vitresyn™ Transparent plastics such as polycarbonate and acrylic have the potential to replace glass in a number of applications, car headlamps and spectacle lenses for example. However, these plastics are relatively soft materials and need protection against abrasion and scuff damage. This recently developed system gives good protection at acceptable cost