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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.

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 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.

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.

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.

This SAE Standard establishes the test conditions and reporting method for quantifying refrigerant circuit oil circulation rate (OCR) reduction effectiveness of mobile air conditioning compressors using R-134a and R-1234yf refrigerants that include oil separators and/or other design features for the purpose of reducing the OCR in the refrigerant circuit. This standard and the OCR values it produces are not intended to make judgement on suitability of OCR values with regard to compressor durability.

This SAE Standard establishes the test conditions and reporting method for quantifying refrigerant circuit oil circulation rate (OCR) reduction effectiveness of mobile air conditioning compressors using R-134a and R-1234yf refrigerants that include oil separators and/or other design features for the purpose of reducing the OCR in the refrigerant circuit.

This SAE Recommended Practice provides test methods for determining the characteristics of acoustical and thermal materials. Where applicable, methods of test developed by SAE and ASTM have been referenced.

This specification covers a nitrile (NBR) rubber in the form of sheet, strip, tubing, extrusions, and molded shapes.

This specification covers a nitrile (NBR) rubber in the form of sheet, strip, tubing, extrusions, and molded shapes.

This specification covers a nitrile (NBR) rubber in the form of sheet, strip, tubing, extrusions, and molded shapes.

This specification covers a nitrile (NBR) rubber in the form of sheet, strip, tubing, extrusions, and molded shapes.

This specification covers a nitrile (NBR) rubber in the form of sheet, strip, tubing, extrusions, and molded shapes.

This specification covers a nitrile (NBR) rubber in the form of sheet, strip, tubing, extrusions, and molded shapes.

This specification covers a nitrile (NBR) rubber in the form of sheet, strip, tubing, extrusions, and molded shapes.

This specification covers a nitrile (NBR) rubber in the form of sheet, strip, tubing, extrusions, and molded shapes.