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This research focuses on study of feasibility of using ceramic oxide coatings on the cylinder wall of hypoeutectic aluminum silicon alloy engine blocks. Coatings are achieved in an aqueous electrolytic bath and composed of both alpha and gamma phases of Al2O3 and have shown promising wear resistance. Composition and acidity level of the electrolyte creates a variation of surface roughness, coating hardness and thickness which has direct influence on the wear behavior of the sliding surfaces. The effect of load bearing and coating morphology on coefficient of friction was studied. SEM images of the substrate showed no predominant wear behavior or delamination. Coefficient of friction and wear rate were also measured. This study shows the importance of surface structure on oil retention and wear rate. Coarser coatings can be desirable under starved oil condition since they show lower coefficient of friction.

This paper compares the emissions performance of four ultra thin wall ceramic substrates with standard wall thickness product on a chassis dynamometer for two different substrate volumes. This comparison helps establish performance trends and provides useful information for selection of substrates in designing catalytic converter systems. This experimental study tests and compares four ultra thin wall products (400/4, 600/3, 600/4, and 900/2) with a standard wall product (400/6.5) at two different substrate volumes. Engine bench aging is used to simulate typical aged conditions. Temperature data as well as second by second and bag emissions data for hydrocarbons, carbon monoxide and oxides of nitrogen were used to evaluate the relative performances of the substrates. The US FTP and US06 driving cycles were used as protocols for the comparison. Results suggest that lower bulk density and higher geometric surface area interact to lead to lower emissions.

Experimental forms of two different types of engine oil viscosity sensors have been tested that use uniformly poled disks of piezoelectric PZT ceramic. In both cases, the disks were used to form electromechanical resonators functioning as the frequency-controlling element in a transistor oscillator circuit. The simpler type of sensor used only one disk, vibrating in a radial-longitudinal mode of vibration. In this mode, a disk 2.54 cm in diameter and 0.127 cm thick had a resonant frequency of approximately 90 kHz. The second type of sensor used two such disks bonded together by a conducting epoxy, with poling directions oriented in opposite directions. This composite resonator vibrated in a radially-symmetrical, flexural mode of vibration, with the lowest resonant frequency at approximately 20 kHz. The presence of tangential components of motion on the major faces of both resonators made them sensitive to the viscosity of fluids in which they were immersed.

An extremely tough alumina based ceramic coating produced by a modified anodizing process developed at Moscow Aviation Institute has been evaluated for light weight, wear resistant component applications in automotive powertrain. The process details and test results from comparative evaluation of friction and wear properties for cylinder bore application, referenced to cast iron baseline, are presented and discussed.

Because it is common to attach plastic parts to other plastic, metal, or ceramic assemblies with mechanical fasteners that are often stronger and stiffer than the plastic with which they are mated, it is important to be able to predict the retention of the fastener in the polymeric component. The ability to predict this information allows engineers to more accurately estimate length of part service life. A study was initiated to understand the behavior of threaded fasteners in bosses molded from engineering thermoplastic resins. The study examined fastening dynamics during and after insertion of the fastener and the effects of friction on the subsequent performance of the resin. Tests were conducted at ambient temperatures over a range of torques and loads using several fixtures that were specially designed for the study. Materials evaluated include modified-polyphenylene ether (M-PPE), polyetherimide (PEI), polybutylene terephthalate (PBT), and polycarbonate (PC).

Using instrumentation designed for the ultrasonic measurement of thickness, a technique has been devised for measuring the isotropic elastic constants of small samples, i. e., samples 1 mm in thickness and a minimum of 5 mm in other dimensions. Young's modulus, the shear modulus and Poisson's ratio are calculated from measurements of density and ultrasonic shear and longitudinal wave velocities. Samples of valve train materials, including chill cast iron, low alloy steel, tool steel, stainless steel, a nickel-base superalloy, and a powder metal alloy were machined from components and analyzed. The magnitude of the measured values of the elastic constants are reasonable when compared with published values. The measurement error on all the constants is estimated to be less than 1%. Moduli determined by this method can be used in finite element analyses to improve designs.

A hydrocarbon trapping system for cold start emissions was constructed and tested using two types of carbonaceous adsorbents provided by Corning, Inc. One was made by combining activated carbon with an organic binder and extruding it into a honeycomb, and the other by depositing a carbon coating on a ceramic monolith. The tests were carried out on an engine in a dynamometer laboratory to characterize the performance of the carbon elements under transient cold start conditions. Performance was evaluated by continuously measuring exhaust gas hydrocarbon concentrations upstream and downstream of the trap, using conventional emissions consoles. Samples were also collected for off-line analysis of individual hydrocarbon species using gas chromatography to examine differences in adsorption of individual species. The speciated hydrocarbon data were used to distinguish between the mass trapping efficiency and a reactivity-based trapping efficiency of the adsorbant traps.

Cavitation thresholds of 5W30 and 10W30 oils were measured in laboratory experiments using electrically-driven disks of piezoelectric ceramic as sources of mechanical excitation. The technique allows the mechanical-wave power density at which cavitation begins to be observed and calculated from electrical quantities and the volume of the oil sample being tested. Both cavitation turn-on and turn-off thresholds have been measured as functions of temperature and frequency. The temperatures ranged from 20 to 100°C and the frequencies ranged from 50 kHz to 4 MHz. The experiments have shown these oils can be made to undergo cavitation at surprisingly low thresholds.

Four regenerator matrix samples, fabricated by different manufacturing methods and consisting of different ceramic materials and cell geometries, were studied to determine their reliability and performance potential in a typical industrial gas turbine engine. Hypothetical regenerators were designed from these matrix samples to give identical engine performance, and the thermal stress was determined for each. In some instances, it was necessary to stress relieve and preload the rims in order to reduce the thermal stresses so that acceptable reliability could be obtained. The four hypothetical regenerators were then compared on the basis of size, cost, leakage, etc., so that the advantages of each configuration could be observed. The performance and reliability analysis was based on Ford Motor Company's shuttle rig performance tests and over 200,000 core-hours of engine test on ceramic regenerators. The engine test program is described in detail.

The paper reviews our problems of energy availability in the middle and long-term future as well as our problems of environmental pollution and materials availability. Against this background the ceramic gas turbine engine is examined and shown to have potential as an attractive candidate powerplant for both the middle and long-term future. The paper reports on Ford's ceramic gas turbine program which is a systems development program encompassing all aspects of turbine ceramics technology---design, materials, fabrication processes, testing and evaluation.

The development of vehicular gas turbine engines to operate at temperatures up to 2500°F has been in progress for some time. The purpose of this paper is to review the rationale behind this engine, to highlight the major hot flowpath components being developed, and to provide information on the progress of this program.