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Engine oils are subjected to a series of industry standard engine dynamometer tests to measure their wear protection capability, sludge and varnish formation tendencies, and fuel efficiency among several other performance attributes before they are approved for use in customer engines. However, these performance attributes are measured at the end of tests and therefore, do not provide any information on how the properties have changed during the tests. In one of our previous studies it was observed that engine oil samples collected from fleet vehicles after 12,000 mile drain interval showed 10-15 % lower friction and more importantly, an order of magnitude lower wear rate than those of fresh oils. It was also observed that the composition of the tribochemical films formed was quite different on the surface tested with the drain oils from those formed with fresh oils.

Diesel exhaust systems equipped with selective catalytic reduction (SCR) catalysts based on urea were subjected to an aging process where the exhaust gas temperature was below 300°C. Solid deposits related to urea injection were found on the wall of the exhaust pipe down stream of the urea injector and on a urea mixer in front of the SCR catalyst. In laboratory tests, an aqueous solution of urea (1.5wt%) was dripped onto an SCR catalyst core in a simulated lean gas mixture at a rate corresponding to a 1:1 NH3-to-NOx ratio (NOx = 350ppm) and a space velocity (SV) of 15,000 h-1 at various temperatures. At 300°C and below, urea-related deposits appeared on the SCR catalyst surface and totally plugged the SCR catalyst monolith within 250 hours. When the aging temperature was 350°C or above, no deposits were observed on the SCR catalyst core.

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 liquid, while burning on a cold surface, can dissolve significant amounts of its combusion products. After reaction with a suitable solid surface, these products are identifiable by infrared spectroscopy. Corrosion derived in this manner can be quantified gravimetrically. Thus, steel corrosion from methanol combustion was measured by burning several layers of the alcohol on a steel coupon, while recording the coupon weight. Corrosion enhancement by fuel contaminants, such as sulfur or peroxide, was measured by this method, as well as, corrosion inhibition by cofuels and lubricant layers. The flaming coupon test is also suitable for comparing corrosion resistance of metals as a function of alloy composition, or for ranking protective coatings. Some of the corrosion fundamentals involved in the rust formation during this test are analyzed.

Polyurethane foam material for use in future vehicles were evaluated for their potential to contribute to light scattering films (LSF), Methods used included the fog test, infrared analysis for amines, and development of a technique for gas chromatographic analysis of organic extracts of foams. Process amines, including 1,3,5-tris (dimethylamino) pentane, were detected in two samples. Acetonitrile was found to be the most effective of six organic solvents for both direct extraction of foam and washing the film sample from the glass used in the fog test.

Chemical analysis of the light scattering film (LSF) formed on interior glass surfaces of automobiles has been undertaken to identify the significant contributing species. Much of the LSF was found to be stable organic compounds, emanating from materials in the vehicle interior, and condensing on the glass. Some compounds found were actually produced by chemical reaction on the glass. The qualitative and quantitative nature of this film was extremely variable. Environmental conditions have been found to contribute to composition of these films. To identify, and reduce or eliminate the contributing materials appears to be the best means to control the LSF.

Burning methanol produces formic acid, which can cause steel corrosion at temperatures below the dew point of the exhaust gas. Because of the potential of methanol as an alternate automotive fuel, it is of interest to evaluate the conditions, which can aggravate or mitigate the extent of this rust formation. Rust formation is promoted by such methanol contaminants, as organic chloride and peroxide. The effects of these species on rust formation were measured quantitatively as a function of concentration by the application of burning methanol in a simple, novel coupon test. Rust formation can be inhibited by cofuels or by lubricants. Effects of Indolene Clear and of other methanol cofuels were measured by the coupon test as a function of concentration. Corrosion protection by engine oil was evaluated as a function of acid-neutralizer concentration and layer thickness.