Viewing 1 to 30 of 574
Technical Paper
Jeffrey Nichols
The focus of Cost Competitive Light-weight materials is a significant and relative objective for Commercial Vehicle Manufacturers and Component Suppliers. The continued development of ultra-high strength materials to offer improved strength, durability, and mass reduction with a cost competitive position, is a primary emphasis within engineering activities globally. This cost competitive light weighting focus has expanded significantly in all areas of commercial vehicle segments, impacting both powertrain and chassis applications. The focus is largely driven from the direct correlation of reduced vehicle mass to improved vehicle fuel efficiency, Co2 and Nox reduction, as well as safety and overall improvements to durability and performance. The primary challenge to determine the optimal lightweight material is multifaceted in effort to meet all imperative load criteria, while simultaneously providing mass savings in a globally scalable cost competitive solution.
Technical Paper
Sreedhar Reddy, Vignesh T Shekar
There have always been different approaches when it comes to ‘Bus body architecture’. The design approach has gone through different phases namely, chassis based, semi integral, integral and monocoque. Equally varied is the choice of material for bus super structure. The predominantly used ones are - mild steel with galvanization, stainless steel (SS) and aluminum. This paper discusses the rationale behind choosing stainless steel for the complete bus structure. With rapid development in infrastructure and public mass transit system, it has become imperative to have a robust structure for buses that is durable and crash worthy. Among the family of stainless steels, ferritic stainless steel exhibits excellent mechanical properties with corrosion resistance and better strength to weight ratio compared to the galvanized mild steel.
Technical Paper
Zhigang Wei
Corrosion resistance is an extremely important technical issue for long-term durability and reliability performance of exhaust components and systems. Failure mechanisms, such as corrosion, fatigue, corrosion-fatigue and stress corrosion cracking, have long been recognized as the principal degradation and failure mechanisms of vehicle components and systems under combined mechanical and corrosive environmental conditions. The combination of fluid flow, introduced by components such as advanced injectors, and corrosive environment leads to corrosion-erosion failure mechanism. These failure mechanisms are strongly material, environment, and loading dependent. How to characterize, screen, rank and select the materials in corrosion resistance is a big challenge posed to materials scientists and engineers. In this paper, the common corrosion related failure mechanisms appearing in auto exhaust systems are reviewed first.
Technical Paper
Matt Kero
The commercial vehicle industry has seen regulations create new requirements over the last few years. Reductions to stopping distance, improvements to vehicle emissions, and the overall need for lighter weight vehicles has caused the commercial vehicle industry to look for new solutions to meet these needs. One such solution is light-weight aluminum metal matrix composite (MMC) brake drums. Aluminum MMC brake drums create the opportunity to reduce weight, lower brake temperatures, improve brake life cycle, and improve brake performance. During the evaluation of these aluminum MMC components it has been seen that existing procedures do not create accurate comparisons for this new material. Current procedures were designed and implemented for cast iron braking solutions. This paper will outline two procedures; FMVSS121 dynamometer burnishing and SAE J2115 wear performance testing, that do not allow direct comparisons from brake system to brake system to be made.
Technical Paper
Teuvo Maunula, Arto Viitanen, Toni Kinnunen, Kauko Kanniainen
The emission regulations for mobile applications become stricter in Euro-IV to Euro-VI levels. Carbon monoxide and hydrocarbon can be removed by efficient Diesel Oxidation Catalysts (DOC) but Particulate Matter (PM) and NOx are more demanding requiring the use of active methods (urea-SCR and DPF) which will be world-wide implemented in the 2010's. Durable, coated V-SCR catalysts are based on stabilized raw materials and tailored preparation methods. Coated V2O5/TiO2-WO3 catalysts (ceramic 300/400 cpsi and metallic 500/600 cpsi) were evaluated by laboratory and engine bench experiments. Traditional V-SCR catalysts are durable up to about 600°C and have a high efficiency at 300°C-500°C. SCR activities were tailored to be higher also at 200°C-300°C or 500°C-600°C. The use of thermal stabilizers or the vanadium loading variation enabled the changes in operation window and stability.
Technical Paper
Sylla Benedicto Abibe Aranha, Edgard Fernandes de Andrade, Eliana Mitiko Katayose, Kaísa Couto Machado, Marcelo Gonçalves
The truck body on chassis for dry freight applies to several types of goods, including packagings, broken or unitized cargoes. In Brazil, this equipment is traditionally made of wood and recently of steel. Moreover, in overseas countries the manufacturing of aluminium bodies is quite common (mainly in Europe and the United States), for economic, operational and environmental reasons, such as: weight reduction and resulting increase in payload capacity of the vehicle; easy manufacturing and repair; recyclability of the material used. This paper presents the main features and technical requirements from the Design of a Aluminium Truck Body mounted on a 3-axle truck, with 23 tons of deadweight (Gross Weight) and 5.4m of distance between axes.
Journal Article
Xin Lei, Antoun Calash, John Cagney
A cyclically pressurized hydraulic component made of compacted graphite iron (CGI) is examined in fatigue design. This CGI component has a notch, formed at the intersection of two drilling channels. This notch causes the stress to be locally elevated and may potentially serve as a fatigue initiation site. Traditional fatigue design approaches calculate the maximum stress/strain range acting at the notch and apply the Neuber correction when calculating fatigue life. It is, however, found that the fatigue life is dramatically underestimated by this method. This prompts the use of the critical distance method because the stresses are concentrated in a relatively small volume. When using the critical distance method, the fatigue life is correctly predicted. Finally, a fracture mechanics model of the crack check the reasonableness of the critical distance method results.
Technical Paper
Irene Begsteiger, Klaus Richter, Eberhard Jacob, Gerhard Emmerling
A new type of catalyst for exhaust emission control of Diesel engines has been developed by a catalyst producer in cooperation with engine/heavy duty truck manufacturers. This so-called Sorption/Oxidation (“SO”)-catalyst is an extruded TiO2-type and works as a HC-trap as well as oxidation catalyst for hydrocarbons. In addition, a certain amount of particle matter was reduced, depending on type of engine, fuel sulfur content and test cycle. Due to its unique composition, i.e. oxides of titanium (80 wt %), tungsten and vanadium, the catalytic selectivity results in very low formation of sulfates as well as excellent resistance against sulfur compounds. The geometry of the catalyst prototypes corresponds to standard monoliths of 5,66″(144mm) in diameter and suitable lengths to be installed in standard mufflers. Since 1996, several buses and trucks have been equipped with SO-catalysts and are still in operation without problems.
Technical Paper
K. Dröder, St. Janssen
In all areas of engineering in which masses have to be extremely accelerated, parts of magnesium wrought alloys represent a promising solution. Sheet metal forming at elevated temperature and precision forging as near net shape technology have a great potential to become important manufacturing processes for magnesium.
Technical Paper
Jochen Eitel, Gerald T. Woerner, Scott Horoho, Oliver Mamber
The Aluminum radiator has a number of features that make it very attractive for vehicle applications in general. Superior durability and reliability in conjunction with its excellent specific values for costs, performance and weight warrant a favorable solution for Heavy Duty Trucks. Behr has been supplying Aluminum radiators for trucks in Europe for over 10 years and in North America for 4 years. This paper examines the results based on this long-term experience. It reviews the field experience compared to Copper/Brass radiators, examines design and mounting features as well as the manufacturing processes. Durability, external and internal corrosion resistance are emphasized as essential characteristics. A special focus is the thermodynamics of Aluminum radiators. The paper reviews methods to simulate the thermodynamic behavior of radiators and the progress in the specific performance, based on the development of improved radiator core matrices.
Technical Paper
Suresh Babu Muttana, Arghya Sardar, Sajid Mubashir
Sustainable mobility has become priority in the wake of environmental concerns viz. emissions and depletion of fossil fuels. The growing demand for more fuel-efficient vehicles to reduce energy consumption and air pollution is a challenge for the automotive industry. Significant improvements in fuel economy can be obtained by weight reduction of vehicle as well as by improvements in engine and powertrain efficiency. If the vehicle body mass is reduced, there will be secondary mass reductions at the component level, particularly in the powertrain. Globally, automotive manufacturers have been engaged in efforts to develop lighter alternatives using aluminium alloys and other light weight materials, so as to reduce the energy requirement, improve the fuel consumption and reduce vehicular emissions. While the growth in mobility is growing rapidly in India, the installed base is still comparatively small, compared to the developed countries.
Technical Paper
Edney Rejowski, Edmo Soares, Samantha Uehara
The demand for higher output performance engines has lead to the increase of PCP (Peak Cylinder Pressure) and more aggressive engine designs for cylinder liners, mainly for new heavy duty engines developments where low cost components are been introduced. Such trends have generated demands to adequate the liner design by improving its material properties by changing its chemical composition, new materials data or even by introducing more accurate casting manufacturing process. Therefore, there is a clear tendency to development more and more alternative solutions that combine a certain technical high-value added and low cost. The most important material properties for cylinder liners are the ultimate tensile strength (UTS) and the fatigue tensile strength. Both parameters confer to the cylinder liners, especially for wet top flanged designs, the ability to survive under high mechanical and thermal load conditions even with reduced wall thickness.
Technical Paper
Sandro Victor Polanco Espezua, Carlos Antonio Reis Pereira Baptista, Denise Ferreira Laurito, Ana Marcia Barbosa da Silva
Due to their favorable properties, among them the excellent strength-to-weight ratio, aluminum alloys are applied in transport vehicles, like trucks and buses. With respect to their mechanical behavior, fatigue is a process that alters the life of a structural component producing local stresses and floating strains and consequently giving rise to crack nucleation and the fracture of the material. In this work it is shown the influence of microstructure and intermetallic particles in aluminum alloy AA6005-T6, AA6063-T6 and AA6351-T6 that were tested for tension and fatigue. The microconstituents and the crack path on the fracture surfaces were analyzed by optical microscopy and scanning electron microscopy (SEM). The variation of the geometry of the precipitated particles of Mg₂Si, intermetallics (Fe,Mn)₃SiAl₁₂ and irregular distribution of particles in the matrix of the alloys were observed.
Technical Paper
Matt Kero, Thomas Hewer, Jeremy Zills
The use of Aluminum Metal Matrix Composites (MMC's) is becoming a viable solution to help meet the new regulations of the medium to heavy-duty truck markets. The objective of this paper is to present both analytical and dynamometer data that demonstrate the damage tolerance of a selectively reinforced Aluminum MMC brake drum. In particular, dissimilar coefficients of thermal expansion (CTEs) between the MMC and Aluminum portion of the drum results in favorable compressive stresses in the Aluminum. This state of stress facilitates the slowing of crack growth for flaws whose depth reaches the boundary between MMC and Aluminum. This paper will present an analytical study utilizing finite-element models to predict stress levels in a drum subject to thermal and mechanical loading. Examination of the stress-fields for braking events at room temperature and elevated temperature provides evidence of the aforementioned compressive stresses in the Aluminum portion of the drum.
Technical Paper
Shinji Fujii, Takayuki Sunakawa, Akiko Abe, Masanobu Fukushima, Kenji Kawaguchi, Shigeru Ogawa
This paper clarifies aggressivity reduction approach for MPV, Multi-Purpose Vehicles, derived from large passenger vehicles toward small passenger vehicles. The effects of aggressivity-reducing approach were measured through full-frontal rigid barrier crash simulations with TRL aluminum honeycomb by Finite Element Method. The front-end structures of large vehicles studied in this paper based on this aggressivity reduction approach show good front-end homogeneity and low average height of force. The structures were also found to effectively reduce aggressivity toward small vehicles by car-to-car simulation. However, there are some cases where the effect was influenced by overlap ratios. From this result, overlap ratio is considered to be one of the important factors to improve compatibility performance.
Technical Paper
Federico Ballo, Roberto Frizzi, Gianpiero Mastinu, Donato Mastroberti, Giorgio Previati, Claudio Sorlini
Abstract In this paper the lightweight design and construction of road vehicle aluminum wheels is dealt with, referring particularly to safety. Dedicated experimental tests aimed at assessing the fatigue life behavior of aluminum alloy A356 - T6 have been performed. Cylindrical specimens have been extracted from three different locations in the wheel. Fully reversed strain-controlled and load-controlled fatigue tests have been performed and the stress/strain-life curves on the three areas of the wheel have been computed and compared. The constant amplitude rotary bending fatigue test of the wheel has been simulated by means of Finite Element method. The FE model has been validated by measuring the strain at several points of the wheel during the actual test. From the FE model, the stress tensor time history on the whole wheel over a loading cycle has been extracted.
Technical Paper
Muthuraj Ramasamy, Vignesh E, Sundararajan Thiyagarajan
Abstract A “WHEEL” is one of those auto component in a vehicle which necessitates equal attention from safety, ergonomics and aesthetic perspectives. A conventional tube type wheel for commercial vehicles is made of steel with steel side rings (multi-piece construction). In course as headway in wheel design the single piece wheels were developed which used the tubeless tires. These wheels were made available in both steel and aluminum versions. Wherein the aluminum wheels were lighter in weight than steel, aesthetically more appealing and had other significant advantages. Despite the advantages of these tubeless tire wheels, the end user had to invest for both wheels and tubeless tires to replace conventional tube type steel wheels. The retro-fitment calls for higher exchange cost of wheel and tire and this process stands to be more capitalistic to the end user wherein the payback period was longer.
Technical Paper
Torbjörn Narström
Abstract The use of modern quenched and tempered steels in dumper bodies to reduce weight to increase the payload and reduce the fuel consumption is briefly discussed. Modern quenched and tempered steels in combination with adopted design concept will further increase weight savings of the dumper body. Use of these materials may lead to 4 times longer wear life than ordinary steels. One of the main load cases for a dumper body is impact of an object, i.e. boulders and rocks, into the body. A well-proven test setup is used to develop a model to predict failure and depth of the dent after the impact. A material model with damage mechanic was utilized to predict fracture. The developed model was used to study the effect of the geometry of the impacting object, thickness of the plate and unconstrained plate field. The model was also implemented in larger model and compared with a full scale test of dumper body.
Technical Paper
Timo Björk, Ilkka Valkonen, Jukka Kömi, Hannu Indren
Abstract The development of weldable high-strength and wear-resistant steels have made modern structures such as booms and mobile equipment possible. These sorts of novel and effective designs could not be constructed with traditional mild steel. Unfortunately, the use of these novel steels requires proper design, and there is no practical design code for these novel steels. This paper addresses stability issues, which are important considerations for designs with high-strength steels, and the properties of the heat-affected zone, which may require special attention. Fatigue design is also discussed in this paper, and the importance of the weld quality is highlighted, along with discussions on which details in the weld are the most important. By comparing the test results with the classical load limit solution, it is determined that full plastic capacity is reached and that the samples display good strain properties.
Technical Paper
Suresh Kumar Kandreegula, Naveen Sukumar, Sunil Endugu, Umashanker Gupta
Abstract To compete with the current market trends there is always a need to arrive at a cost effective and light weight designs. For Commercial Vehicles, an attempt is made to replace existing Gear Shift Fork from FC Iron (Ferro Cast Iron) to ADC (Aluminum Die Casting) without compromising its strength & stiffness, considering/bearing all the worst road load cases and severe environmental conditions. ADC has good mechanical and thermal properties compared to FC Iron. Feasible design has been Optimized within the given design space with an extra supporting pad for load distribution. Optimization, Stiffness, Contact pattern has been done using OptiStruct, Nastran & Ansys for CAE evaluation. A 6-speed manual transmission is used as an example to illustrate the simulation and validation of the optimized design. Advanced linear topology optimization methods have been addressed as the most promising techniques for light weighting and performance design of Powertrain structures.
Technical Paper
Rohitt Ravi, Sivasubramanian, Bade Simhachalam, Dhanooj Balakrishnan, Krishna Srinivas
Abstract Tubular stabilizer bar for commercial vehicle is developed using advanced high strength steel material. Tubular section is proposed to replace the existing solid section. The tubular design is validated by component simulation using ANSYS Software. The tubes are then manufactured of the required size. The bend tool is designed to suit the size of the profile stabilizer bar and the prototypes are made using the tube bending machine. The strength of the tubular stabilizer is increased by using robotic induction hardening system. The tubular stabilizer bar is tested for fatigue load using Instron actuators. Higher weight reduction is achieved by replacing the existing solid stabilizer bar with the tubular stabilizer bar.
Technical Paper
Anjana Deva, S K De, A K Bhakat, B K Jha, S Mallik
Abstract High-strength steels are a cost-efficient means of reducing the weight not only of premium-segment cars but also of light, medium and heavy commercial vehicles. Lighter a vehicle, lower its fuel consumption and the lower its CO2 emissions during driving. Depending on part and use, high-strength steels permit weight savings of up to 30 percent. In this way steel makes a key contribution to sustainable mobility. Innovative high-strength steels allow auto components to be made thinner and thus lighter without sacrificing safety. A wide range of application oriented automotive grades have been developed at SAIL. Despite their high strength, these materials are readily formable and can be processed without difficulty at auto stamping plants. The challenge with these materials is that high strength and good formability are usually mutually exclusive. This conflict is resolved with solutions such as special alloying elements.
Journal Article
Ryoji Suzuki, Yukihide Yokoyama, Takeo Shibano, Tatsuki Sugiura, Noriaki Katori
Abstract 1 One issue raised by the use of austenitic stainless steels in commercial vehicles is the increase in material costs. To reduce those material costs, a nitric acid electropolishing treatment was applied to SUS436L (18 Cr - 1.5 Mo - 0.4 Nb) and corrosion tests were conducted to compare its corrosion resistance to that of SUS316L(16 Cr - 12 Ni - 2 Mo). Compared to SUS316L, SUS436L subjected to nitric acid electropolishing indicated superior corrosion resistance. In addition, XPS and TEM analyses showed that while the SUS436L passivation film layer contained approximately twice as much chromium, its thickness was also generally reduced by approximately half, to 2 nm. These results suggest that electropolishing with nitric acid, which is highly oxidative, formed a fine passivation film.
Technical Paper
Matt Kero
Rising fuel costs, shorter stopping distance requirements, and the growth in hybrid vehicles all lead to an increased demand in lightweight vehicle components. Changing market needs generate innovative products. One innovative product is a lightweight aluminum metal matrix composite (MMC) brake drum that is substantially lighter than the traditional cast iron product. The objective of this paper is to present the lightweight brake drum using both analytical and dynamometer data to demonstrate the effectiveness during speed sensitivity testing. Thermal analysis tools were developed to predict brake temperatures. These predictions utilize system parameters and braking event characteristics to create realistic predictions of temperature, which have been validated with dynamometer testing. This paper will also present dynamometer data that shows the effectiveness of braking events at varying brake speeds and system pressures.
Technical Paper
V. R. M. Gonçalves, L. C. F. Canale, V. Leskovšek, B. Podgornik
Abstract Spring steels are the materials most commonly used in suspensions of vehicles and are subject to heavy efforts in terms of load, impact and also under intense fatigue solicitation. Required mechanical performance depends mainly on the chemical composition and heat treatments. Therefore, the aim of the present work was to compare SAE 5160 steel with one Super Clean steel developed in Slovenia. Searches improving mechanical properties of these steels are constantly present in the automotive industry, reducing vehicle weight and maintaining safety. In this scenario, cryogenic treatment in combination with quenching and tempering has shown interesting results in the scientific literature for tool steels and the best results for cryogenics are achieved when the treatment occurs for long duration as 24 hours.
Technical Paper
W. C. Weltman
Abstract The larger the equipment for a specific job in the earth-moving field, the more quickly and efficiently that job can be done. Unfortunately, the very size and weight of many present units means that the transportation of them involves a ponderous task. If increased capacity could be obtained with no increase in gross vehicle weight, and with only negligible differences in dimensions, major progress could be made in the equipment field. Even if physical dimensions involved no problem, the weight and placement of such essentials as tires, wheels, brakes, drive chains and engines, all tend to limit the payload capacity of a given vehicle. Through the judicious use of aluminum alloys in proved applications, a 10 to 15 per cent increase in payload capacity can readily be achieved at no increase in gross vehicle weight. The aluminum applications referred to have been proved both in over-the-road and in off-highway service.
Technical Paper
Technical Paper
S. Ghosal, B. R. Galgali, M. M. Ogale, S. P. Joshi
The bake hardening effect depends on three parameters i.e. pre-straining, paint baking temperature and paint baking time. The combined effect of all these parameters results into the increase in yield strength, called the “baking effect”. This paper explains the individual effects of these parameters on the baking value. Tensile test were carried out for the 495 samples baked at baking temperature from 140°C to 250°C with differential baking time of 10, 15, 20, 25 and 30 minutes and differential pre-straining of 2%, 3% and 5%. The differences of yield strength between the unbaked and baked sample were calculated and the increase in yield strength was noted. After these laboratory trials 800 numbers of door outer panels of a small truck were formed and finish painted. The increment in yield strength after component forming and painting was determined by taking tensile samples from three different locations of 5 painted doors.
Technical Paper
Reimund Neugebauer, Michael Seifert, Petr Kurka, Andreas Sterzing
Due to the need for a significant reduction in the weight of parts in automotive manufacturing, the use of lightweight materials such as magnesium and aluminium is becoming increasingly important. Unfortunately, these materials are often associated with limited cold formability. Because of this, production of large, complex sheet metal components using forming technology frequently entails greater cost. To extend the application of these materials in manufacturing processes, it is essential to identify strategies which permit improvement of the forming behaviour of these materials. The use of elevated temperatures as a process parameter in forming operations is a strategy which has potential in terms of the search for a solution to counter the aforementioned disadvantages. Firstly, it permits a distinct increase in the ductility and formability of the material. Secondly, it reduces deformation resistance and hence the forming forces and pressures required.
Technical Paper
Hong Lin, Robert R. Binoniemi, Gregory A. Fett, Thomas Woodard, Mick Deis
To improve fuel economy and possibly reduce product cost, light weight and high power density has been a development goal for commercial vehicle axle components. Light weight materials, such as aluminum alloys and polymer materials, as well as polymer matrix composite materials have been applied in various automotive components. However it is still a huge challenge to apply light weight materials in components which are subject to heavy load and thus have high stresses, such as gears for commercial vehicle axles or transmissions. To understand and illustrate this challenge, in this paper we will report and review the current state of art of carburized gear steels properties and performance.
Viewing 1 to 30 of 574


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