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(Paint) film as an alternative to spray applied paint has received growing attention in recent years. The potential for economic and environmental advantage and quality enhancement with this technology has been reported in several technical papers (Ref. 1, 3 and 4). The actual practice of film finishing, however, has received only limited notice. Film finishes have been applied to aluminum, stainless steel, PVC, and ABS. Starting in 1982, part applications include: wheel covers, door edge guards, window surrounds, roof drip moldings, lower windshield moldings, rocker panels, body side moldings, B pillars, and A pillars. Industry awareness and acceptance of film finishing as a viable alternative to spray applied paint is increasing. The two technologies are similar in many ways, yet distinctly different in other ways. They share a common goal: To yield a durable finish, economically and with superior visual impact. This paper reviews the unique aspects of film finishing.

A 1.8L turbocharged diesel engine valvetrain friction was investigated, and the effectiveness of using a solid film lubricant (SFL) coating in reducing friction was determined throughout the operable speed range. This valvetrain design features direct acting mechanical bucket valve lifters. Camshaft journal bearing surfaces and all camshaft rubbing surfaces except lobe tips were coated. The direct acting bucket shims were etched with a cross hatch pattern to a depth sufficient to sustain a SFL film coating on the shim rubbing surfaces subjected to high surface loads. The SFL coated valvetrain torque was evaluated and compared with uncoated baseline torque. Coating the cam bearing journal surfaces alone with II-25D SFL reduced valvetrain friction losses 8 to 17% for 250 to 2000 rpm cam speed range (i.e. 500 - 4000 rpm engine speed). When bucket tappet and shims were also coated with the SFL, further significant reductions in coated valvetrain friction were observed.

A 10 KWe dual-mode space power system concept has been identified which is based on INEL's Small Externally-fueled Heat Pipe Thermionic Reactor (SEHPTR) concept. This power system will enhance user capabilities by providing reliable electric power and by providing two propulsion systems; electric power for an arc-jet electric propulsion system and direct thrust by heating hydrogen propellant inside the reactor. The low thrust electric thrusters allow efficient station keeping and long-term maneuvering. The direct thrust capability can provide tens of pounds of thrust at a specific impulse of around 730 seconds for maneuvers that must be performed more rapidly. The direct thrust allows the nuclear power system to move a payload from Low Earth Orbit (LEO) to Geosynchronous Earth Orbit (GEO) in less than one month using approximately half the propellant of a cryogenic chemical stage.

An advanced low heat rejection engine concept has successfully completed a 100 hour endurance test. The combustion chamber components were insulated with thermal barrier coatings. The engine components included a titanium piston, titanium headface plate, titanium cylinder liner insert, M2 steel valve guides and monolithic zirconia valve seat inserts. The tribological system was composed of a ceramic chrome oxide coated cylinder liner, chrome carbide coated piston rings and an advanced polyolester class lubricant. The top piston compression ring Included a novel design feature to provide self-cleaning of ring groove lubricant deposits to prevent ring face scuffing. The prototype test engine demonstrated 52 percent reduction in radiator heat rejection with reduced intake air aftercooling and strategic forced oil cooling.

The increased use of recycled resins can create a dilemma for automotive designers. On the one hand, there is a growing initiative to increase recycled materials content on vehicles, globally. On the other hand, traditional methods of recycling polymeric materials -both thermoplastics and thermosets - can lead to degradation of engineering, mechanical, processing, and / or aesthetic properties of the resin. In an era where quality rules, this situation forces designers to accept a much lower percentage of recyclate than they might otherwise wish to use or risk unacceptable property loss in molded parts - something no automaker can “afford ” for long. Hence, a valuable feedstream of materials (polymers) often ends up destined for a landfill once many consumer products are broken down and more easily reusable or recyclable materials are salvaged. As a case in point, each passenger car built globally contains an average of 15 - 20 kg of nylon polymers.

The increased occurrence of environmental damage to automotive topcoats and the variety of abrasive conditions to which the coating is subjected have made increasing demands on the properties of these coatings. There is as yet, no single paint chemistry that fulfills these extreme requirements in all respects. On the other hand, the right choice of components in polyurethane can result in excellent etch resistance as well as improved scratch resistance compared to traditional melamine/acrylic systems. This paper will discuss some recent studies in the areas of two-component and one-component polyurethane chemistry, which address these rigorous quality requirements.

General Motor's Corvette product engineering was given the challenge to find mass reduction opportunities on the painted body panels of the C6 Z06 through the utilization of carbon fiber reinforced composites (CFRC). The successful implementation of a carbon fiber hood on the 2004 C5 Commemorative Edition Z06 Corvette was the springboard for Corvette Team's appetite for a more extensive application of CFRC on the C6 Z06 model. Fenders were identified as the best application for the technology given their location on the front of the vehicle and the amount of mass saved. The C6 Z06 CFRC fenders provide 6kg reduction of vehicle mass as compared to the smaller RRIM fenders used on the Coupe and Convertible models.

This paper describes the after-treatment technology that could be used to meet a future BS-VII standard, considering close-coupled SCR (cc-SCR) to help start NOx conversion earlier. Both active (Cu/Fe-SCR based) and passive (V-SCR based) systems have the potential to meet emission limits. V-SCR may be considered in the rear position because V-SCR shows a fast response with very low N2O formation. Next-gen V-SCR technology shows significantly improved performance and durability closer to Cu-SCR. The steady-state NOx conversions over Next-Gen V-SCR were better than BS-VI V-SCR in both fresh and aged-580°C/100h conditions. High durability was also observed after engine aging of 1000h (WHTC + high load). Another big challenge in BS VII could be the PN10 requirement. With enhanced filtration coating (EFC) technology, PN emissions drop drastically in comparison to Euro VI reference without EFC to meet a future BS VII.

Durability tests have been initiated on olefinic and production painted fascias. Both 2D and 3D tests have provided insights into Friction Induced Damage (FID) failure mechanics. Full scale, 3D tests of automotive fascia mimic the parking lot rubbing contact between cars with friction forces exceeding 5000. N. 2D tests provide the cost effective approach to materials research by isolating the failure mechanics in the upper 250 μm of the decorated TPO where the cosmetic damage is initiated. Initial findings show some olefinic paint, TPO combinations to be more damage resistant for realistic frictional contact scenarios.

2k clearcoat is the progressive step that is keeping coatings for elastomeric fascia in pace with the current automobile design, performance, and durability demands. Initially, rigid 2k coatings were applied over plastic for low temperature cure. Over metal, 2k rigid clearcoat produced a dramatic improvement in appearance and durability. Flexibility is the key attribute that a 2k clearcoat engineered for use over fascias must posses. Utilizing the same basecoat and primer, 2k flexible clearcoats are being successfully applied to flexible fascia, generating excellent appearance and outstanding durability.

The upcoming latest 3-wet Technology is the most ideal design for a Green field project as well as for a brown field facility which provides the best of both worlds. The foremost take away for a brown field project emanates from this technology which demands a smaller foot prints & hence could accommodates a capacity higher than what was perceived during the green field project planning thus saving millions of dollar of investment & giving that extra capacity which today the BRIC countries are thriving for. Apart from making the ideal investment choice, 3 Wet Technology provides impetus to business case in terms of reduction of VOC emission, Energy consumption, Material and labor cost and gaining on Green Environment front as well as leading to smart and Efficient-Paint-Process. The paper depicts the journey of roll out of 3-Wet process in Ford India and creating the bench mark in terms of product quality and process standards and manufacturing practices.

Multi-layer steel (MLS) cylinder head gaskets are becoming more widely used to seal an engine. Therefore, it is important to understand the interaction between the engine head, block and head gasket. While experimental methods for determining necessary gasket tightening loads and experimental data relating some gasket design parameters to failure are available, it is very costly and time consuming. A numerical method, such as the finite element (FE) method, has proven to be very useful and efficient in aiding gasket design. A 3D engine FE analysis can predict a number of parameters. Of particular interest are the motion as well as the contact profile of the head, block and gasket. This information, usually difficult or impossible to obtain from a 2D FE analysis, can be used to predict the two most common failure modes of a gasket, fatigue crack and leakage.

Coated refractory metals, coated and alloyed graphites, hafnium-tantalum alloys, refractory borides, and stabilized zirconias are considered for the 3600–4000 F high-velocity air environment. Only refractory borides and stabilized zirconias are indicated as offering long duration and reuse capabilities for such high-temperature utilization. Iridium, as coatings on substrates of either graphites or refractory metals, appears attractive for shorter times (less than 1 hr). Environmental evaluation and the need for a theoretical framework to enable the prediction of performance data for such materials are indicated to be major problems facing users and suppliers.

For the launch of the 800 series ARG set out to maintain the paint on line process for plastic bumpers developed for Maestro and Montego, to achieve this, new and exciting problems had to be overcome. A vehicle weight of 1420kg for the highest derivative, a maximum centreline deflection of 15mm front and rear, a profile collapse calculated to absorb energy within 65% of it's cross sectional area and show no damage within the terms of the ECE 42 regulation, ie 4kph centreline and mounting, 2.5kph corner and a perfect colour match combined with the highest quality.

Flight control technology for 8000 psi has emerged almost simultaneously with new fire-resistant hydraulic fluids, such as MIL-H-83282 and CTFE. A proliferation of industry recommendations has resulted in a wide variety of mechanisms for solving associated actuator design problems, including tighter clearances, special seals, finishes, materials, and many others. As there are few common agreements on the issues, an extensive three-phase test program was undertaken to attempt to corroborate some of these approaches or suggest others that may be better or more cost effective.

With growing concern about global warming, alternatives to fossil fuels in internal combustion engines are searched. In this context, hydrogen is one of the most interesting fuels as it shows excellent combustion properties such as laminar flame speed and energy density. In this work a CFD methodology for 3D-CFD in-cylinder simulations of engine combustion is proposed and its predictive capabilities are validated against test-bench data from a direct injection spark-ignition (DISI) prototype. The original engine is a naturally aspirated, single cylinder compression ignition (Diesel fueled) unit. It is modified substituting the Diesel injector with a spark plug, adding two direct gas injectors, and lowering the compression ratio to run with hydrogen fuel. A 3D-CFD model is built, embedding in-house developed ignition and heat transfer models besides G-equation one for combustion.

A 3D-CFD model with detailed chemical kinetics was developed to investigate the combustion characteristics of HCCI engines, especially those fueled with hydrogen and n-heptane. The effects of changes in some of the key important variables that included compression ratio and chamber surface temperature on the combustion processes were investigated. Particular attention was given, while using a finer 3-D mesh, to the development of combustion within the chamber crevices between the piston top-land and cylinder wall. It is shown that changes in the combustion chamber wall surface temperature values influence greatly the autoignition timing and location of its first occurrence within the chamber. With high chamber wall temperatures, autoignition takes place first at regions near the cylinder wall while with low surface temperatures; autoignition takes place closer to the central region of the mixture charge.

Through an addition of a small amount of hydrogen to the main fuel, combustion process can be considerably enhanced in internal combustion engines producing significantly lower levels of exhaust emissions. This improvement in combustion can be mainly attributed to the faster and cleaner burning characteristics of hydrogen in comparison to conventional liquid and gaseous fuels. An oxygen-enrichment of a fuel-air mixture also improves thermal efficiency and reduces especially particulate, carbon monoxide and unburned hydrocarbon emissions in exhaust. This contribution describes the results of experimental investigation where a small amount of hydrogen and oxygen is produced by Hydrogen Generating System through the electrical dissociation of water and are added to the intake of a compression ignition engine operating on a commercial diesel fuel. It is shown that level of exhaust emissions including NOx can be moderately reduced using such a pre-treatment method in diesel engines.

For fuelling road transportation in the future, particularly light-duty vehicles, there has been much speculation about the use of hydrogen and fuel cells to provide electrical power to an all-electric drive train. An alternative powertrain would use a simple battery to store electricity directly, using power from the electrical grid to charge the battery when the vehicle is not in use. The energy efficiency of these two different approaches has been compared, using a complete “energy conversion chain analysis”. The successful development and introduction into the marketplace of grid-connected hybrid vehicles could eliminate the need for road vehicles to use petroleum fuels, at least for the majority of miles traveled. If electricity were to be generated primarily from sustainable primary energy sources, then road transportation would also become sustainable, resulting in an “Electricity Economy”, rather than a “Hydrogen Economy.

The prime function of crown wheel pinion is to receive the power from transmission & distribute to two-wheel ends. Doing so these members will experience the tremendous bending fatigue. Shot peen is the one of the latest technology used to improve the bending fatigue of the CWP [1]. In this particular case- six CWP are taken for the study to understand the effect of the operations after shot peen process. Three Samples are named as batch A, another 3 samples are named as batch B. Both the batch CWP are shot peened. Then as a regular production practice the batch A CWP are process through hard turning ➔ Abrasive lapping ➔ Hot lubriting (manganese phosphate) ➔ Fully finish ready for assembly. Then both the batch A & batch B samples are taken for residual stress analysis using X-Ray diffraction technique. The measurement location is 50 microns below the surface. The results tabulated, found that batch A samples shows decrease in Residual stress relatively to batch B.