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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.

This paper describes the engineering, manufacturing and integration necessary to produce the Corvette's first ever all-aluminum spaceframe (see Figure 1). The engineering and manufacturing of the spaceframe was a joint venture between General Motors and suppliers ALCOA (Aluminum Company of America) and Dana Corporation. ALCOA led the initial design of the spaceframe; Dana Corp led the manufacturing; General Motors' Engineering and Manufacturing groups led the integration of the assembly. The aluminum spaceframe design is modeled after the baseline steel structure of the Corvette coupe. The aluminum spaceframe reduces 140 lbs from the steel baseline and enters the plant at 285 lbs. This frame allows the 2006 Corvette Z06 to enter the market at a 3100 lbs curb weight. Aluminum casting, extruding, stamping, hydroforming, laser welding, Metal Inert Gas (MIG) welding, Self Pierce Riveting (SPR), and full spaceframe machining make up the main technologies used to produce this spaceframe.

A 3D computer model named AIPAC (Aircraft Ice Protection Analysis Code) suitable for thermal ice protection system parametric studies has been developed. It was derived from HASPAC, which is a 2D anti-icing model developed at Wichita State University in 2010. AIPAC is based on the finite volumes method and, similarly to HASPAC, combines a commercial Navier-Stokes flow solver with a Messinger model based thermodynamic analysis that applies internal and external flow heat transfer coefficients, pressure distribution, wall shear stress and water catch to compute wing leading edge skin temperatures, thin water flow distribution, and the location, extent and rate of icing. In addition, AIPAC was built using a transient formulation for the airfoil wall and with the capability of extruding a 3D surface grid into a volumetric grid so that a layer of ice can be added to the computational domain.

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.

A five-year development program by the American Metal Products Co. to process stamped axle housings has culminated in the application of cold extrusion to spindles. The new process involved the installation of a 5500 ton press capable of driving a punch through a 20 lb billet, as well as modification and rearrangement of existing equipment. The system has not only resulted in considerable production savings but has also contributed to an overall expansion program. The company, although fully preoccupied with the basic spindle for production of axle housings, has already investigated other applications of the new equipment toward product diversification.

Catalytic combustion coupled with activated carbon and molecular sieve adsorbents is applicable to all areas of air and gas clean up ranging from high to low levels of pollutants and trace contaminants control in a spacecraft environment is of no exception. In this study we propose a combined activated charcoal and catalytic combustion system based on a 70 watt power input achieving 350°C, operating on a 6 hour per 24 hour day catalytic cycle with an actual flow of 10.6 l min-1 in a residual free volume of 60 m3.

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.

A new heat resistant aluminized steel, trade named ALUMA-TI, has been developed which has unique mechanical and corrosion properties especially attractive for high temperature applications where economy is a prime consideration for material selection. Presented are its mechanical properties and response to various corrosive environments. High temperature strength and oxidation resistance is far superior to Type I ALUMINIZED steel at temperatures above 704°C (1300°F). In combined oxidation/corrosion tests, ALUMA-TI is comparable to AISI 409 stainless steel. Therefore, ALUMA-TI is a prime material candidate for automotive exhaust systems.

The adoption of turbine engines for automotive power plants has been hampered by the high cost, high leakage and high wear rate of present designs of ceramic-matrix regenerators. Proposals are made and analyzed here for design directions to achieve substantial improvements in all three areas. These include lower-cost extruded and pressed matrices; and clamping seals coupled with incremental movement of the rotary-regenerator matrix.

The use of modularized aluminum extrusions for the block, crankcase and head in small engine systems allows a range of engines to be mass produced without resort to casting for the stationary components. The use of modern accurately dimensioned extrusions greatly reduces the machining required. The versatility and strength of extruded aluminum alloys enables the elimination of load bearing threads and most other finish machining, thus significantly reducing the labor costs of manufacture. A range of strokes and hence of different capacity engines can be produced from a single extrusion form. For extended life, bores can be coated with a variety of finishes, including simple anodizing. Extrusion technology allows cost-effective engines to be manufactured with a significantly lower investment than with other technologies.

In this paper, a new diesel particle filter material made from silicon carbide sintered in a liquid phase is presented. The sintering process allows for controlling of certain parameters that influence the extrusion process, the material properties and hence the filtering characteristics. Furthermore, using triangular channel geometry to build up a wall flow filter makes it possible to have a newly segmented geometry that leads to hexagonal shaped filter cartridges. A variety of on the market available wall flow filter materials are compared with data about material porosity, particle size distribution, strength, specific filtration surface as well other parameters influencing the filtration efficiency. The material characteristics gathered are analyzed and evaluated.

A new method has been developed to close the ends of a wall flow filterused for removing particulate matter from diesel engine exhaust. In thismethod, the ends of the honeycomb structure are capped by deforming andclosing the ends of the channel walls between the extrusion and firingstages of production. The method increases the amount of filtration area per filter volume for agiven cell geometry conpared to the traditional plugging method, since theentire length of the honeycomb channels is used for filtration purposes. In addition, use of the capping method has a beneficial effect on thepressure loss characteristics of a filter with a given filtration area.These benefits are illustrated through experimental results.

A new proportional collection system for extremely low tailpipe emission measurement in transient conditions has been developed. The new system can continuously sample a minute flow of exhaust gas, at a rate that is proportional to the engine exhaust rate. A zero grade gas dilution technique is utilized to prevent the influence of pollutants in atmospheric air that are the same concentration level as those in the exhaust gas. The system has accuracy within ±5%. For the direct exhaust gas flow meter, a pitot tube type flow meter is utilized as it is simple, heat resistant, sufficiently accurate and has low flow-resistance characteristic. For the collection and dilution controllers, two mass flow controllers (MFC) were adopted. The MFCs' output can be adversely influenced by variation of the specific heat of the sample gas, resulting in flow reporting error.

Presenting a brand new approach to heat exchangers for engines, transmissions, hydraulic systems, etc. This new heat exchanger is made of only two pieces of circular extruded aluminum profiles: Core and shell. No soldering: The core and the shell is assembled by a minimum of automated work. In an oil to water cooling application, the active surface on the oil side of the core is enlarged by fins 0.2 mm thick, 0.3 mm spacing, and 3 mm high. The fins are made in unique production machines and enlarge the active surface area approximately five times compared to a conventional heat exchanger of the same dimensions. The principle utilizes the low pressure drop at laminar flow and avoids the disadvantage of low heat transfer after a certain laminar flow length. The result is approximately three times higher oil heat dissipation, combined with very low oil pressure drop, compared to conventional technique.

Constrained layer damping (CLD) is a well known technique to efficiently damp low frequency vibration. CLD employs a viscoelastic material sandwiched between two very stiff, typically metal, layers. While effective over essentially flat surfaces, CLD has not been applicable to cylindrical shapes. In order to damp low frequency vibration in metal pipes, users have been forced to rely on extensional layer damping, typically consisting of thick layers of extruded or molded rubbers. This paper discusses a novel product to damp cylindrical articles such as metal pipes with a constrained layer heat shrink tubing. This product utilizes a stiff heat shrinkable polymeric jacket bonded on the inside with a viscoelastic layer. When shrunk on a metal pipe or rod, a CLD system is produced. The product is typically thinner than an extensional layer damper and is more effective. It also meets the other physical and environmental requirements for a pipe covering.

Normal microphones can't resist high temperatures. The recently developed particle velocity microphone, can resist temperatures up to 300 degrees Celsius (570 degrees Farenheit). Current R&D is focused on increasing the upper temperature of the sensor element to 600 degrees Celsius (1300 degrees Farenheit). A sound pressure (p) sensitive system is created with a particle velocity sensor, when it is placed in a small (4cm in length and 5mm in diameter) standing wave tube. This sound pressure arrangement is combined with a particle velocity sensitive (u) element and thus creating a pu (intensity) probe. All components of this novel sensor are made with special heat resistant materials. A model of the temperature dependence is derived and checked by measurements. The frequency response, polar pattern, selfnoise etc. of both pressure and velocity microphone are determined.

One of the major characteristics of paper-based wet friction materials used for clutch plates and brake bands in automotive automatic transmissions is represented by their resilient and porous properties. This specific characteristic is considered to govern the tribological behavior between a paper-based friction material and a mating steel surface. In this paper, the effects of porosity and resiliency on the friction characteristics and heat resistance of paper-based friction materials were studied. Significant direction was obtained by the experimental data of this study, which may be adapted to the design of friction plate materials.

We studied new-type heat-resistanct elastomers. They are based on fluoroelastomer/ acrylic-elastomer blands. Their heat resistance temperature for long term use are about 175°C. They are graded E to F class for heat resistance and G to H class for oil resistance within the ASTM D2000/SAE J200 framework. In this presentation, newly developed elastomers are discussed.

Three different rapidly solidified Ni-Mo-Fe-B alloys were produced by chill block melt spinning. The ribbons were pulverized, then consolidated by extrusion after being heated for 2 hours at 1100°C. The consolidated specimens were aged isochronally in the range of 400°C to 1100°C for 1 hour, and the age hardening behaviors were studied. Additionally, the extruded alloys were age hardened under an optimized heat treatment condition of 800°C for 4 hours. The microstructures, room and elevated temperature hardnesses, and wear properties of the alloys were evaluated for a possible application to high performance automotive engines.