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Performance measures such as static roll stability, rearward amplification and load transfer ratio are a means to assess the engineering performance of heavy vehicles and to support truck size and weight policy decisions. It was expected that, for a particular vehicle configuration, there would be some degree of correlation between the various performance attributes. For example, a relatively high static roll stability may be associated with a relatively low load transfer ratio, at least within a particular vehicle configuration. In terms of developing performance measures such correlations are of great significance because (i) the number of performance attributes requiring specification may be reduced and (ii) potential conflicts between performance criteria in different attributes may be avoided. This type of analysis has not been carried out before, and requires a large database of performance numerics in order to determine relationships between each of the performance attributes.

A study was made on the nature of the weld interface obtained in resistance welding of component leads used in electronic packages. To this end an investigation was made comparing the microstructure, microhardness, and microchemistry of a variety of cross wire resistance welds. Specifically, the investigation concerned itself with the variations in microhardness, and microchemistry at and near the weld interface as a function of metallographic structure, distance from the interface, and type of material being welded. This study will help answer such questions as the amount of diffusion of one weld component into another, the effects of welding on the mechanical properties near and adjacent to the weld, and provide for a more intelligent interpretation of the variety of microstructures that have been observed. The results of this work can be summarized as follows: 1. There is little or no diffusion of one material into the other.

Fifty-six ride tests of class 8 COE vehicles were conducted. Linear correlation was investigated between subjective jury ratings and each of 12 objective ride measures that were calculated from vertical and longitudinal cab acceleration measurements. Ninety-five percent confidence band-widths and correlation coefficients were used to compare the correlation of each ride measure to the jury ratings. The ride measure defined as: had the highest correlation, while the unweighted longitudinal rms acceleration correlated only slightly less well. Significantly lower correlation was obtained for the ride measures investigated containing longitudinal Absorbed Power or ISO weighted longitudinal rms acceleration. No significant degree of correlation was obtained for unweighted vertical rms acceleration, vertical Absorbed Power, or ISO weighted vertical rms acceleration.

The performance of elastomeric radial lip seals for rotating shafts and hub applications can be correlated to the texture of the wear track on both trimmed and molded sealing lips. Seals with rough wear tracks have an abundance of microasperities that provide good pump rates and excellent service reliability. Seals with smooth wear tracks have no microasperities, poor pump rates and poor service reliability. The pumping ability of seals with smooth wear tracks can be enhanced for a short time by artificially roughening the wear tracks. Pumping ability and service reliability can be improved by changing elastomeric material formulations to provide microasperities in the wear track.

At The Queen's University of Belfast there has been, for some twenty years, a continuing program of research into scavenging flow in two-stroke cycle engines, recently using a single-cycle gas scavenging apparatus. This apparatus has been demonstrated to give accurate assessments of the scavenging efficiencies of such engine cylinders. The apparatus utilises a constant volume, isothermal flow process in the experimental simulation of the scavenging flow and, as many of the classic theories of scavenging are similarly formulated, this provides a unique opportunity to compare theory and experiment on the basis of equality of procedure. This paper presents experimental data for the scavenging characteristics of uniflow-, loop-and cross-scavenged two-stroke engine cylinders and compares the measurements with the classic theories of scavenging as presented by others in the literature.

From May, 1977 to May, 1978, the Transportation Centre, University of Saskatchewan conducted four surveys to determine seatbelt usage rates in Saskatchewan. The surveys were conducted prior to and after, the passage of a law on July 1, 1977, requiring seatbelt use by front seat occupants of motor vehicles. The surveys were conducted at sampling stations on urban streets, provincial highways and municipal roads. The results of the May, 1978 survey were analyzed to determine what relationships exist between usage rates and various vehicle characteristics. Usage rates when examined using cross-tabulations appeared higher for certain types of vehicles: compact or sub-compact vehicles, foreign models, etc. However, when the data was analyzed using multiple regression techniques, only the year of vehicle manufacture showed a consistently high level of significance.

Lunar and planetary programs have entered the surface exploration research phase. In this phase, considerable emphasis is needed on high mobility vehicle configurations, reliability and high efficiency, low weight electrochemical energy converters, and electric traction power systems. This research, in many cases, is applicable to solving future mobility problems on earth. Three areas of current lunar and terrestrial research are discussed and analyzed, and the correlative advantages to those working in both fields are highlighted. The three areas are; (1) high mobility vehicle configurations; (2) electrochemical energy converters; and (3) electric traction power systems.

Samples of painted cold rolled and galvanized steel have been exposed to laboratory cyclic and salt spray tests, accelerated outdoor exposure in Florida, and on a vehicle in Detroit. Samples have been evaluated visually and by scanning electron microscopy and microprobe analysis. Galvanized steel performed better than cold rolled steel in all but the salt spray test. Some of the factors influencing the spread of corrosion beneath a paint film have been identified.

Government clean air regulations have prompted much interest in the automotive industry in alternative fuels for lower emission vehicles. Methanol fuels have become the primary focus of the auto companies in meeting these challenges. Even though the corrosiveness of methanol and commercial methanol fuel blends is well recognized, no systematic investigations on the relative corrosion behavior of metals and their coatings in these solutions are available. The purpose of the present study is to determine the relative corrosion rates for metals, plated metals, and otherwise coated metals that were exposed to ionic and water contaminated methanol/gasoline fuel mixtures. The results are described for samples that were immersed in M15 and M85 test fuels for between 2000 to 8000 hours under static laboratory conditions at 40°C. The primary measure of corrosion was mass loss, which was used to generate corrosion rates, where possible, for each of the specimens.

An extensive field study was made of the corrosion of aluminum alloy panels in over fifteen years of service in three regions of the USA. Panels removed from service exposed vehicles were subjected to further testing to determine the relationship between field service, accelerated laboratory corrosion testing, and marine environment exposure for two years at Daytona Beach, Florida. In addition, two 42 year old aluminum bodied Dyna Panhard vehicles were recovered in France, examined closely, and subjected to similar tests. Few examples of significant corrosion were found in the field, and only one example of filiform corrosion on aluminum sheet in service. Steel panels on the same vehicles frequently rusted through, and filiform corrosion was seen occasionally. Laboratory tested aluminum panel samples frequently showed filiform corrosion and severe intergranular corrosion.

A proving ground trailer test was conducted on twenty trim materials mounted to three different body panel substrates. The trim materials tested include a detailed stainless steel evaluation, chrome flashed and nickel/chrome plated stainless steels, stainless steel bilaminates, bimetal, and plated rolled zinc. The body panel substrates were cold rolled steel and 60G60G and 70G70G electrogalvanized steel. The trim materials were tested in grounded and isolated conditions to determine the galvanic interaction with the body panel substrates. The test data has been correlated to field surveys in Detroit and Montreal for further validity (1)*.

A powder coating is a fine powder which melts, flows, and forms a continuous film as heat is applied. Due to the nearly 100% non-volative nature of powders, higher molecular weight resins can be utilized to increase the corrosion and chemical resistance of the coating. In addition, solvents, amines, and other volatiles associated with conventional liquid coatings are not employed and cannot be trapped in the cured film. Due to this basic polymer chemistry, powder coatings normally provide superior corrosion resistance to their liquid counterparts. While powder coatings have been successfully utilized in the automotive industry, their use has been limited. Current products offer many proven advantages, and future developments may even further increase their effectiveness.

One joining technique that is receiving increased attention is mechanical fastening with a steel self-piercing rivet. The use of steel rivets in direct contact with aluminum components raises questions concerning galvanic corrosion. To determine if a corrosion problem exists, aluminum samples were joined by two processes--resistance spot welding and steel self-piercing rivets. Replicate samples using two aluminum alloys were tested for 90 days by alternate immersion in 3.5% NaCl water solution. After alternate immersion exposure, the integrity of the joint was evaluated by shear testing. Joint shear strengths and the metallographic corrosion evaluations are presented in this paper.

This paper is an introduction to the basic manufacturing techniques utilized in «Air Brazing of Aluminum Automotive Heat Transfer Products» and the relationship to the corrosion resistance of products manufactured with this process.

In order to investigate the corrosion resistance of organic composite-coated steel sheets ( OCS ) in a real automotive environment, many kinds of corrosion tests were performed on test pieces and real automotive doors. Tests with a corrosive solution including iron rust were introduced to simulate the real corrosive environment of automotive doors. The relationship between the components of OCS and the corrosion resistance in the rust-including tests was examined. In addition, electrochemical studies were performed. Results indicate OCS has much better corrosion resistance than plated steel sheets with heavier coating weight in all tests. OCS shows excellent corrosion resistance in rust-free corrosive solution, however, some types of OCS do have corrosion concerns in rust-including tests. It became clear that these OCS types have an organic coating with lower cross-linking.

The change from gasoline to alternate fuels such as those based on methanol, is expected to create material compatibility problems because of the enhanced reactivity of the powder metal (P/M) materials currently in use. These problems are most serious for the steels containing copper or those that have been copper infiltrated. P/M austenitic stainless steels offer the possibility of overcoming the inherent corrosion problems of the current P/M alloys. Test samples of 304L and 316L were processed on production equipment and sintered in pure hydrogen or a simulated dissociated ammonia mixture. Corrosion testing was performed in SAE-approved mixtures of “aggressive methanol” and gasoline (termed CM15A and CM85A). To accelerate the corrosion test and simulate an auto-oxidized fuel mixture, a small amount of t-Butyl Hydroperoxide was added. These preliminary tests confirm that Fe-0.8 %C and Fe-2% Cu-0.8%C steels will rust in these test fuels, within 24 hours.

In this work, the type and level of strain are related to the degree of corrosion resistance and the type of coating damage for three coatings: 40 gm/m2 electrogalvanized steel, 80 gm/m2 electrogalvanized steel and Zincroplex™, a zinc-rich paint over 40 gm/m2 electrogalvanized steel. The coating weight of the electrogalvanized steels was a factor in the degree of coating damage and thus affected corrosion resistance. The electrogalvanized steels were adversely affected by bi-axial deformation. Zincroplex™ failed under draw-type deformation. Although the corrosion limit diagram technique does not predict service life, it can distinguish among the capabilities of different materials at different levels and types of strain.

This paper presents the engineering technology for the 1992 Corvette Acceleration Slip Regulation (ASR) system and Antilock Brake System (ABS). After the introduction of Bosch 2S anti-lock brakes in the 1986 Corvette, we experienced an improvement in vehicle stability and steerability during hard braking. The next challenging task was to improve the vehicle's stability during acceleration. The goal was to assist the driver of this high horse power front engine, rear wheel drive sports car on low coefficient surfaces. This goal was accomplished with the functional integration of engine torque management and brake intervention. This required functional integration of three subsystems: engine spark retard, throttle close down and brakes. This is the first application for a throttle close down device which provides driver feed back of slippery road conditions, through the accelerator pedal.