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A laboratory study was performed to assess the effects of sulfur poisoning and desulfation temperature on the NO conversion of a LNT+(Cu/SCR) in-situ system. Four LNT+(Cu/SCR) systems were aged for 4.5 hours without sulfur at 600, 700, 750, and 800°C using A/F ratio modulations to represent 23K miles of desulfations at different temperatures. NO conversion tests were performed on the LNT alone and on the LNT+SCR system using a 60 s lean/5 s rich cycle. The catalysts were then sulfur-poisoned at 400°C and desulfated four times and re-evaluated on the 60/5 tests. This test sequence was repeated 3 more times to represent 100K miles of desulfations. After simulating 23K miles of desulfations, the Cu-based SCR catalysts improved the NO conversion of the LNT at low temperatures (e.g., 300°C), although the benefit decreased as the desulfation temperature increased from 600°C to 800°C.

A task group within the SAE Automotive Corrosion and Protection (ACAP) Committee continues to pursue the goal of establishing a standard test method for in-laboratory cosmetic corrosion evaluations of finished aluminum auto body panels. The program is a cooperative effort with OEM, supplier, and consultant participation and is supported in part by USAMP (AMD 309) and the U.S. Department of Energy. Numerous laboratory corrosion test environments have been used to evaluate the performance of painted aluminum closure panels, but correlations between laboratory test results and in-service performance have not been established. The primary objective of this project is to identify an accelerated laboratory test method that correlates with in-service performance. In this paper the type, extent, and chemical nature of cosmetic corrosion observed in the on-vehicle exposures are compared with those from some of the commonly used laboratory tests

Improvement of engine fuel efficiency through the use of low friction engine oils is a major task in engine lubrication research. This friction reduction can be achieved by improving the rheological characteristics and elastohydrodynamic (EHD) properties of engine oils, and by controlling boundary chemical interactions between oil-based additives and lubricated components in the engine. In order to achieve minimal frictional power loss under all lubrication regimes, engine tribological systems must be designed to effectively use advanced lubricant technology, material and surface modifications. This paper presents results of cooperative research addressing opportunities for minimizing friction through extension of hydrodynamic lubrication regime in lubricated components using various formulation approaches. A set of experimental oils has been evaluated using laboratory test rigs that simulate hydrodynamic, EHD, mixed and boundary lubrication.

Meeting upcoming stringent emission standards will require that exhaust gas catalyst systems become active very quickly, function at very high efficiencies and maintain those capabilities at high mileages. This means that contamination of the catalysts by engine oil derived poisons must be minimized. Phosphorus compounds, derived from the zinc dialkyldithio-phosphate (ZDTP) additives that provide antiwear and antioxidant activity, are a principal contaminant that can increase catalyst light off times and reduce catalyst efficiency. Therefore, reducing the concentration of, or eliminating, phosphorus in engine oils is desirable. Doing so, however, requires that oils be reformulated to ensure that wear protection will not be compromised and that oxidation stability will be maintained. To address these concerns, laboratory tests for evaluating oil oxidation and wear performance have been developed and used to evaluate developmental low phosphorus oils.

The pneumatic air brake system for heavy commercial trucks is composed by a large number of components, aiming its proper work and compliance with rigorous criteria of vehicular safety. One of those components, present along the whole vehicle, is the air brake tube, ducts which feed valves and reservoirs with compressed air, carrying signals for acting or releasing the brake system. In 2011, due to a lack of butadiene in a global scale, the manufacturing of these tubes was compromised; as this is an important raw material present on the polymer used so far, PA12. This article introduces the methodology of selecting, developing and validating in vehicle an alternative polymer for this application. For this purpose, acceptance criteria have been established through global material specifications, as well as bench tests and vehicular validation requirements.

A vehicle system to monitor the actual condition of engine oil in service would provide the customer with the opportunity to utilize the full useful life of the oil and would minimize problems which can occur when oils remain in the engine too long and are excessively degraded and/or contaminated. This paper describes limitations of some systems which have been proposed, outlines the requirements and potential difficulties related to development of sensors designed to monitor changes in chemical properties of the oil, and describes laboratory and vehicle evaluations of a candidate sensor.

Painting is the most difficult, the most costly, and the most polluting step in manufacturing vehicles. When low weathering performance paints are used, the results are dissatisfied customers, and huge warranty costs. It would obviously be wise to fully characterize the weathering performance of new coatings systems before they are used. Unfortunately this is not always practical. Coating formulations are changing rapidly in the States to comply with solvent emission regulations, the introduction of plastic substrates, and customer tastes. There is rarely enough time to wait ten years for outdoors exposure tests to reveal the "true" weathering performance of coatings before marketing vehicles. As a result, accelerated tests are often used to guide decisions. However, the results of such tests can be misleading because the harsh exposure conditions used can distort the chemistry of degradation.

A method was adapted to measure the adhesion strength of polyurethane, semi-flexible foams to thermoplastic substrates. This method (lap-joint shear) was used to determine the effect of six (6) variables upon adhesion. These variables were: 1.) the type of substrate material, 2.) the type of polyurethane foam, 3.) the weight percentage of water in the polyurethane formulation (the degree to which the foam is blown and the chemical constituents), 4.) the chemical index of the polyurethane (the ratio of isocyanate to polyol resin), 5.) the surface roughness of the substrate, and 6.) the temperature of the polyurethane materials. Five (5) typical automotive interior thermoplastic substrates were studied: 1.) Polypropylene with preblended glass, 2.) Polycarbonate/ABS, 3.) PPO/HIPS with preblended glass, 4.) SMA with in-house dry blended glass, and 5.) SMA with preblended glass.

The presence of a foreign substance on or within a polymer often affects the mechanical, chemical and thermal properties of the material. The change in strength and rigidity of a polymer resulting from the plasticizing action of a sorbed chemical or due to the withdrawal of an added plasticizer by the leaching operation can seriously affect the useful life of the material. In the real engineering world, incompatible chemicals and lubricants get onto various plastic components unexpectedly through design, manufacturing processes, customers services and repairs. This paper presents a number of case-studies which illustrate how undesirable chemicals found on plastic parts can affect product performance and cause damage to the parts.

Erosion damage to automotive car bodies caused by stones and small sand particles and road debris significantly affects the appearance of paint. Painted engineering plastics as well as precoated sheet steel are affected by erosion phenomenon. Erosion of painted plastic substrates results in cosmetic concerns while that on metal substrates results in cosmetic to perforation corrosion. This work describes a laboratory simulation of erosion of painted plastic substrates by small particles on various paint and substrate types. Gloss loss was used to quantitatively evaluate erosion of painted surfaces. Wear behavior of painted plastic substrates to slag sand impact was evaluated as a function of several variables including paint type (one-component melamine crosslinked (1K) vs. two-component isocyanate crosslinked (2K)), thermal history, and coating modulus. The effect of slag sand type (particle size and chemical composition) was studied.

Vehicle interior noise due to powerplant radiation is a product of two factors, the noise level radiated by the powerplant and the effectiveness of the vehicle body and sound package in reducing this noise. Effective noise reduction strategies require that the appropriate target levels be set for these factors. This paper reviews studies performed at Ford to establish such targets and the theoretical basis of these studies. To set sound package targets engine noise simulators have been used to study the sound package noise reduction capabilities of various vehicles. These studies include the effect of noise source location on attenuation, the effect of powerplant location and dimensions, and the effect of interior microphone location. Engine noise targets are being established by testing powerplants in the hemi-anechoic dynamometer test cells of the new AEC Building. Studies include the effect of engine rpm, load, and microphone location.

This paper presents a validation project carried out by the Ford Motor Company and Numerical Integration Technologies (NIT) concerning the numerical prediction of engine noise radiation. The importance and the difficulty of building a structural model (predicting accurate vibration data) are discussed. A new methodology has been developed. This method consists of a modal expansion of experimental data and allows to introduce experimental vibration measurements in the numerical approach to enhance the quality of the predictions. Provided that the structural behavior is correctly assessed, the project has shown that the BEM-based acoustic predictions agree remarkably well with test data.

This paper summarizes some of the research which has been carried out at Ford Motor Co. in the area of NOx traps. Results from a large body of experimental work are reviewed and used to provide insight into the fundamental processes which govern NOx trap performance. In particular, the key parameters which control thermal durability and sulfur poisoning of the NOx trap are discussed in detail. In addition, a theoretical model of the NOx trap is described and used in the analysis and interpretation of the experimental results.

Statistical Energy Analysis (SEA) is being actively pursued in the automotive industry as a tool for vehicle high frequency noise and vibration analysis. A D-class passenger car SEA model has been developed for this purpose. This paper describes the development of load cases for the SEA model to simulate road noise on rumble road. Chassis roll test with rough shells was performed to simulate rumble road noise. Sound radiation from tire patch and vibration transmission through spindles were measured to construct the SEA load cases. Correlation between SEA model predictions and measured data was examined. Test and SEA result comparisons have shown that simulation of airborne road noise requires only a trimmed body SEA model, while simulation of structure-borne road noise may require SEA modeling of chassis components.

PROPER protection of metal parts operating as bearing surfaces, or in contact under relatively heavy loads, during the break-in period often means the difference between successful operation and failure. Various surface coatings have been investigated to discover which ones will give this protection. The authors discuss here three types of surface treatment for cast-iron and steel that do give superior wear and scuff resistance.

Pyrolytic gas chromatography (PGC) has been applied to the characterization of the organic constituents of brake linings. The test involves the pyrolysis of a sample followed by the instrumental separation and sensing of the products of decomposition. A study of experimental variables, such as pyrolysis temperature, has allowed the selection of conditions which yield excellent reproducibility and sensitivity. The preferred test conditions, which have been incorporated in Ford's brake lining quality control specifications, result in a relatively rapid, meaningful test for constancy of composition.

Three techniques for the measurement of the oxides of nitrogen in automotive exhaust were evaluated. These included a “nitrous fume” analyzer, a gaseous NO2 colorimeter, and a movable mass spectrometer. All data obtained were compared to data from currently accepted wet chemical methods, the phenoldisulfonic acid and the “modified” Saltzman. Of the techniques evaluated, the mass spectrometer analysis of NO has been found to be the most useful for the study of nitrogen oxides in engine exhaust. The high cost of wet chemical analysis has indicated a need for an improved and continuous analytical method. The mass spectrometer approach measures NO within seconds of its discharge, thus minimizing any reactions prior to measurement.

Engine dynamometer and laboratory flow reactor studies of automotive catalyst deactivation caused by the use of leaded fuel indicate that there are two different deactivation mechanisms: one, which dominates between 700 and 800 C, is the poisoning of the active platinum sites by lead oxide, or perhaps lead, and the other, which occurs below 550 C, is a build up of a gas diffusion barrier of lead sulfate. Both deactivation mechanisms can be temporarily reversed. Poisoning is reversed when the platinum is freed of lead oxide by lead sulfate formation below 650 C; and the barrier formed below 550 C can be made more permeable by thermal sintering of the lead sulfate at 600 to 700 C or its decomposition to lead oxide at 700 to 800 C. However, further exposure of the catalyst will again render it inactive via the mechanism predominating in that temperature region.

Speciation of sulfurous acid, sulfuric acid and ammonium sulfate collected from the aerosol phase on a Fluoropore filter has been readily accomplished using techniques of chemical ionization mass spectrometry combined with thermal separation. Thermal separation of ammonium hydrogen sulfate from ammonium sulfate was not possible. Spectral separation of these species by selective ionization is proposed. Analysis of sulfate aerosols collected from ambient air and catalyzed vehicle emissions is described. It was found that sulfuric acid aerosol was rapidly converted to ammonium sulfate or ammonium hydrogen sulfate in the presence of ambient concentrations of ammonia. Ambient samples collected in the Detroit metropolitan area have been found to contain only trace quantities of sulfuric aicd. Sulfate samples collected from a dilution tube into which catalyzed vehicle exhaust was injected were found to contain significant quantities of ammonium sulfate in addition to sulfuric acid.

IT is only since World War ll that extensive study has been made of the effects of high-energy radiation on materials. However, a lack of fundamental data still prevents the making of any generalizations or detailed calculations of the effects of radiation-induced defects on the bulk properties of metals. The author discusses the problem from three points of view: 1. The effectiveness of materials in absorbing radiation. 2. The basic mechanisms of the interaction of radiation and matter—in order to determine the changes on the mechanical properties of materials. 3. Radiation as a convenient and economical source of energy for irradiation of chemical systems. The author thinks, on the basis of the limited data available, that one of the most useful effects of radiation on matter has been the use of ionizing radiation to bring about chemical reactions, especially in organic compounds.