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One of the most promising applications for the use of hydrogen in vehicles is in the combustion engine. According to the legislation proposal being considered by European Union, hydrogen internal combustion engines (H2ICE) are zero emissions solution. Among the existing solutions, H2ICE is becoming the preferred one on long haul trucks and offroad applications. This is due to the high durability of the powertrain, the lower initial investment when compared to other alternatives, and the possibility of using low purity hydrogen. However, despite the high potential use of hydrogen, because of it is the smallest known chemical element, its use can result in the penetration of hydrogen into metallic materials, with the undesirable effect of embrittlement. This effect occurs mainly when the material surface is exposed to high temperatures and pressures, or under corrosion.

In comparison to aluminum, Compacted Graphite Iron (CGI) iron has superior mechanical properties, enables the use of parent bore running surfaces and fracture split main bearings, and provides advantageous NVH, package size, cost, and manufacturing CO2 profiles. Despite these advantages, aluminum blocks have leveraged density, and therefore weight, differentials to make considerable gains in the small, in-line passenger vehicle sector over the last 30 years. In order to demonstrate the potential benefits of CGI for small, in-line spark-ignition engines, the present study converted the cylinder block of a series production 1.2 litre three-cylinder engine from aluminum to CGI. Leveraging a novel design concept, with the running surface and load path constructed from high-strength CGI and the outer crankcase housing fabricated from durable, lightweight plastic, the assembled cylinder block achieved the same weight as the original aluminum block.

The electrification of the vehicle fleet has as a direct implication the disposal of lithium-ion batteries. It is noteworthy that such batteries need a suitable destination at the end of their useful life, since they are composed of chemical elements with high added value (such as nickel, cobalt, copper, and lithium) and that cannot be discarded in nature, a since they can generate environmental damage to the ecosystem and to the health of the population. Therefore, the development of effective processes for recycling these batteries is key to the economic and environmental sustainability of vehicle electrification. By recovering critical materials, robust recycling systems reduce raw material demand, greenhouse gas emissions and the environmental impacts associated with mining and refining activities.

With the implementation of Proconve P7, several challenges were faced regarding the integrity of the Power Cell Unit (PCU), which comprehends pistons, rings, cylinder liners, pins, conrods and bearings. The technologies of reducing NOx affect directly the performance of these parts. The systems focused on EGR (Exhaust Gas Recirculation) provoke a higher level of soot contamination in the oil, which creates to all the PCU an abrasion mechanism that leads to the increase of wear load. The systems focused on post treatment of the exhaust gas enables to reach higher PCP (peak cylinder pressure) and higher temperature of combustion. Such conditions are also critical to the PCU combustion, which needs to increase resistance to higher mechanical and thermal loads. Using the experience of Europe and NAFTA some expectations about the environment conditions of Heavy Duty Diesel (HDD) engines after Proconve P7 can be discussed.

Downsized engines are considered one major technical trend to attend the demands for CO₂ and fuel consumption reduction. Usually this engine configuration consists of displacements between 0.9L and 1.2L with 3 or 4 cylinders, usually associated with turbo charge. The increased load due to high gas pressures and power density may affect the PCU components, specially the piston rings. This work reviews the ring pack used on the current downsized engines from European and NAFTA OEMs. The different ring designs and materials used on downsized engines are discussed. The specific challenges that those engines present to piston rings and the available alternatives are discussed. An extreme low friction, under development, ring pack was tested in a 1.2L Turbo downsized engine. With low friction, a low tangential force ring pack, the main issue was control of Lube Oil Consumption.

Changing emission legislation limits are challenging the engine developers in many aspects. Requirement to improve combustion and engine efficiency have resulted in increased loads and higher levels of abrasive particles within the engine environment. Concerning piston rings and piston ring grooves, such engine modifications are leading to critical tribological conditions and side wear is becoming a key issue in the design of these components. Historically one of the most common forms of side wear protection on piston rings has been chromium plate. This solution has limitations on durability (low thickness) and on topography (rough surfaces). In response to these limitations, nitrided stainless steel top rings have been used to improve the side protection; it is harder and typically has a smoother surface finish when compared to chromium coating.

Modern SI engines focusing on CO2 emission reduction has been applying flex fuel technology to enable burning biomass fuels. The prime route is the use of ethanol fuel on these engines. The action of designing an engine to run with ethanol and gasoline (Flex-Fueled Engines) affects powercell components in different ways. The mechanical loads are higher to ethanol fuel. The combustion pressure can be increased without the risk of knocking for ethanol while for gasoline the compression rate of the piston is limited due to knocking occurrence. The spark time also occurs earlier which impacts components lubrication once the maximum load happens near the top dead center (TDC) where the sliding speed is lower and consequently there is lower oil film thickness. Such combination of spark time and sliding speed may also affect dynamics which can affect inertia and load composition of engine components.

With the current use of bio-renewable fuel, the application of Ethanol in Flex-Fuel vehicles presents a very low CO2 emission alternative when the complete cycle, from plantation, fuel production, till vehicle use, is considered. In Brazil more than 80% of the car production is composed of Flex-Fuel vehicles. Due to the lower heating content of the Ethanol, more aggressive combustion calibrations are used to obtain the same engine power than when burning gasoline. Such Ethanol demands, associated with the continuous increase of engine specific power has lead to thermo-mechanical loads which challenges the tribology of piston rings. The ethanol use brings also some specific tribological differences not very well understood like fuel dilution in the lube oil, especially on cold start, corrosive environment etc. Under specific driving conditions, incipient failures like spalling on nitrided steel top rings have been observed.

For years the chromium ceramic coating has proved to have good resistance when applied for Diesel engines subjected to severe operational conditions. However, given the constant increase of engine demands and the concern of low gas emissions, higher wear resistance and durability have been required. As a consequence, MAHLE has developed a new chromium-based coating, which balances the cost competitiveness of chromium-based coatings with enhanced performance. The new coating, named NanoBor Chromium, consists of reinforced chromium coating with ultrafine cBN particles (cBN = cubic boron nitride) embedded inside micro-fissures created by a controlled multi-stage electrochemical process. The tests in MDD engines (MDD=Medium-duty diesel) and HDD engines (HDD= Heavy-duty diesel) have demonstrated the excellent performance of NanoBor Cr as new alternative for heavily demanded application.

The use of Biodiesel is one of the main drivers behind biomass fuels for diesel engine use. This paper compares the performance of powercell components after 100 thousand km field tests using different fuel variants. The tested engine was a 3.0L High Speed Diesel with 120kW @ 3800rpm. Two variants of B5 fuels were tested: one with oil from Soy Bean and other from Castor Bean. Each type of fuel, including regular Diesel, was tested twice. Compared to regular Diesel, the engines tested with B5 presented similar performance [1]. The evaluated powercell parts were: piston, rings, bearings, and cylinder bores. The parts were evaluated in terms of wear, seizure and corrosion. The parts from the B5 tests presented similar visual characteristics after test compared with regular Diesel. A slight wear increase was observed on the parts that ran with the B5 variants. In the case of bearings, corrosion residues were observed with B5 from Castor oil.

Knowledge Management has been recognized as the main way of having higher creative capacity and competitiveness in the companies. The main difficulties of implementing Knowledge Management are the management tool and the company culture. This work presents a tool applied in an automotive company, the MAHLE group. This system has a global use and has around 2000 accesses per month, with peaks of 5000. The tool contains systems for Lessons Learned, Community of Practice, Technical Site, Document Management and a system to collect and flow ideas focused on innovation. The environment in complement of the described applications has been used as main source of distributing information for a global group, technical and/or strategic (restricted access) info. Such information integrates in a global way more than 20 manufacturing plants, 6 R&D Centers and the Sales group.

Due to several market demands of higher wear and scuffing resistance, Duplex PVD (Physical Vapor Deposition) CrN top ring has been used in Heavy Duty Diesel (HDD) engines. The ring comprises a nitrided high chromium stainless steel with a PVD ceramic CrN coating. For High Speed Diesel (HSD) vehicles with lower demands, MAHLE has developed an alternative PVD coated ring, which balances the cost and performance ratio. This alternative, named High Value PVD (HV-PVD), consists of applying the best resistant coating for wear and scuffing, PVD, onto a less costly ring material, Ductile Cast Iron. The HV-PVD top ring has been tested in HSD engines and shown excellent performance. Additional advantages of the HV-PVD are its lower friction coefficient and better tribological compatibility with the cylinder bore materials when compared to the traditional galvanic chrome based coatings. Such features lead to reduced engine friction and lower cylinder wear.

Two electrical fuel pumps were performed with different fuels in two different vehicles. The pumps accumulated 60.000 km and 190.000 km in passenger cars. Both vehicles and pumps were designed to operate exclusively with gasohol (E22), one of the pumps was tested with 60% ethanol in volume of gasoline blend (E60) for 60.000 km from June-2001 to February-2004. The other pump was tested with gasohol (E22) for 190.000 km from August 2000 to February-2004. The test conditions represented the actual use of the vehicles. Such test is not common vehicle manufacturers practice application because it requires a considered long period of time for evaluation procedure. This test helps both the analysis of soak time influence and the running time. This paper presents a tribological analysis of the components in order to compare the influence of both fuels on wear mechanisms or other degradation that could be influenced by the non usual E60 fuel.

An innovative two-piece oil control ring design, named Monoland, has been developed aiming to have high conformability and optimized specific contact pressure. As a result, the Monoland provides superior oil scraping efficiency with reduced friction losses. These were achieved by tailoring the geometrical features and material properties. A solution for oil control rings of minor moment of inertia and higher conformability was achieved through a new geometrical design concept where: a) only one land of the ring is in contact with the bore, b) the outer and inner faces are linked by two convergent planes and by means of a Powder Metallurgy (P/M) steel that was tailored to a lower modulus of elasticity. The new ring design had its structural robustness checked by finite element analysis and its scraping capacity measured by lubricant oil consumption measurement in engine tests.

The two major working characteristics of the oil control ring are: to scrape the lubricant oil from the bore wall in the direction of the crankcase and to maintain a sufficient amount of lubricant oil to the compression rings above it in order to sustain a suitable lubricant film thickness between the rings and the bore. The oil control ring efficiency is the outcome of the combination of the following parameters: the conformability, the pressure against the bore wall, the sort of the contact between the ring and the bore, and the oil scraping dynamics. A new oil control ring, called Monoland®, designed to enhance conformability by making its radial wall more flexible without raising its tangential load is presented in this paper. Moreover, this new ring profile enables the reduction of the tangential load without reducing contact pressure and conformability thus ensuring an ample oil consumption performance with low friction loss.