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Viewing 271 to 300 of 15996
2017-03-28
Journal Article
2017-01-0353
Matilde Scurria, Sinem Emre, Benjamin Möller, Rainer Wagener, Tobias Melz
Abstract Manganese sulfides (MnS) are nonmetallic, ductile inclusions with high melting temperature (1610 °C) which improve the machinability and retard the grain growth in steels, in addition of contributing to avoid cracking during hot working. In this paper, the effect of manganese sulfides on the fatigue life of the vanadium micro-alloyed forging steel 38MnVS6 is discussed. Force-controlled fatigue tests are performed on small sized specimens until the crack occurs. The fatigue life of the forged material, presented by Wöhler curves, is considerably reduced at high levels of the nominal stress amplitude compared to the wrought material. Moreover, it is evident that the presence of longer and thinner particles of MnS reduces the scatter band of Wöhler curves and decreases the fatigue strength of the material. This paper presents a first attempt to find a relation between the shape and content of manganese sulfides due to the forging process and the fatigue life of the material.
2017-03-28
Journal Article
2017-01-0372
Guang Cheng, Kyoo Sil Choi, Xiaohua Hu, Xin Sun
Abstract For multiphase advanced high strength steels (AHSS), the constituent phase properties play a crucial role in determining the overall mechanical behaviors. Therefore, it is important to accurately measure/estimate the constituent phase properties in the research of AHSS. In this study, a new nanoindentation-based inverse method that we developed was adopted in estimating the phase properties of a low alloy Quenching and Partitioning (Q&P) steel. A microstructure-based Finite Element (FE) model was also generated based on the Electron BackScatter Diffraction (EBSD) and Scanning Electron Microscopy (SEM) images of the Q&P steel. The phase properties estimated from nanoindentation were first compared with those estimated from in-situ High Energy X-Ray Diffraction (HEXRD) test and, then, employed in the generated FE model to examine whether they can be appropriately used as the input properties for the model.
2017-03-28
Journal Article
2017-01-0399
Mohammed Yusuf Ali, Wei-Jen Lai, Nikhil Kotasthane, Jagadish Sorab, Chari Sever, Jwo Pan
Abstract In this paper, the results of finite element analyses for nodular cast irons with different volume fractions of graphite particles based on an axisymmetric unit cell model under uniaxial compression and tension are presented. The experimental compressive stress-strain data for a nodular cast iron with the volume fraction of graphite particles of 4.5% are available for use as the baseline material data. The elastic-plastic stress-strain relation for the matrix of the cast iron is estimated based on the experimental compressive stress-strain curve of the cast iron with the rule of mixture. The elastic-plastic stress-strain relation for graphite particles is obtained from the literature. The compressive stress-strain curve for the cast iron based on the axisymmetric unit cell model with the use of the von Mises yield function was then obtained computationally and compared well with the compressive stress-strain relation obtained from the experiment.
2017-03-28
Journal Article
2017-01-0400
Theo Rickert
Abstract Hole drilling is a very common technique for measuring residual stresses. Adding an orbiting motion of the drill was found to improve hole quality in difficult to drill materials and has been in practice for decades. This study compares measurements using various orbiting amounts. Each measurement was repeated twice to evaluate measurement statistics. There is a distinct, though relatively small, effect of the hole shape when no orbiting is used. It disappears already when the hole is 50% larger than the tool size. Different orbiting amounts also produce systematically different results. These may be related to the absolute hole size.
2017-03-28
Journal Article
2017-01-1043
Yang Liu, Tian Tian
Abstract A new ring pack model has been developed based on the curved beam finite element method. This paper describes the first part of this model: simulating gas pressure in different regions above piston skirt and ring dynamic behavior of two compression rings and a twin-land oil control ring. The model allows separate grid divisions to resolve ring structure dynamics, local force/pressure generation, and gas pressure distribution. Doing so enables the model to capture both global and local processes at their proper length scales. The effects of bore distortion, piston secondary motion, and groove distortion are considered. Gas flows, gas pressure distribution in the ring pack, and ring structural dynamics are coupled with ring-groove and ring-liner interactions, and an implicit scheme is employed to ensure numerical stability. The model is applied to a passenger car engine to demonstrate its ability to predict global and local effects on ring dynamics and oil transport.
2017-03-28
Journal Article
2017-01-1271
David Wright, John Henshaw, Nia R. Harrison, S. George Luckey
Abstract High-strength aluminum alloys such as 7075 can be formed using advanced manufacturing methods such as hot stamping. Hot stamping utilizes an elevated temperature blank and the high pressure stamping contact of the forming die to simultaneously quench and form the sheet. However, changes in the thermal history induced by hot stamping may increase this alloy’s stress corrosion cracking (SCC) susceptibility, a common corrosion concern of 7000 series alloys. This work applied the breaking load method for SCC evaluation of hot stamped AA7075-T6 B-pillar panels that had been artificially aged by two different artificial aging practices (one-step and two-step). The breaking load strength of the specimens provided quantitative data that was used to compare the effects of tensile load, duration, alloy, and heat treatment on SCC behavior.
2017-03-28
Journal Article
2017-01-1644
Kinji Taguchi, Misato kusakari, Yasuhiro Akasofu, Jun Yoshimoto
Abstract The weight of wire harnesses increases with the growing number of systems used in the vehicle in recent years. For the purpose of reducing the weight of wire harnesses, aluminum instead of the conventional copper is getting popular as a wire conductor. The conventional Al wire, however, is not able to be used for small gauge wires such as the sizes of 0.35mm2 and 0.5mm2 and wires used in the engine compartment due to its insufficient conductor strength. For this reason, we tried to develop a stronger aluminum alloy that has conductor strength equivalent to or stronger than that of copper. For the first time in the industry, we have successfully developed a high-strength aluminum alloy wire. Starting with the application of 0.35mm2 wire for engine wire harnesses, we began mass production in April 2015. This paper reports the development of high-strength aluminum alloy that can be used for small gauge wires and wires used in the engine compartment.
2017-03-28
Journal Article
2017-01-1705
Hua-Chu Shih, Dajun Zhou, Bruce Konopinski
Abstract The hole piercing process is a simple but important task in manufacturing processes. The quality requirement of the pierced hole varies between different applications. It can be either the size or the edge quality of the hole. Furthermore, the pierced hole is often subject to a secondary forming process, in which the edge stretchability is of a main concern. The recently developed advanced high strength steels (AHSS) and ultra high strength steels (UHSS) have been widely used for vehicle weight reduction and safety performance improvements. Due to the higher strength nature of these specially developed sheet steels, the hole piercing conditions are more extreme and challenging, and the quality of the pierced hole can be critical due to their relatively lower edge stretching limits than those for the conventional low and medium strength steels.
2017-03-28
Journal Article
2017-01-1646
David B. Sarraf, Helge Schmidt
Abstract Aluminum wire is receiving increased attention for automotive applications due to the potential for cost and weight savings. Termination of aluminum wire is problematic due to the tenacious surface oxide on the strands. The oxide is an electrical insulator and is difficult to displace during termination. Consequently, many of the strands within a crimped wire bundle can be electrically isolated from the terminal, which can result in higher than expected crimp resistance, less stable crimp resistance, and the potential for excess heating of the termination. Prior solutions employed additives such as brass powder to puncture the oxide film and form a diffusion bond between strands, or features such as screens or serrations that increase wire deformation and displace the oxide mechanically to promote strand-strand bonding. Both solutions have drawbacks. Additives increase cost and process complexity and can serve as contaminants to adjacent processes.
2017-03-28
Journal Article
2017-01-1047
Yang Liu, Yuwei Li, Tian Tian
Abstract A new ring pack model has been developed based on the curved beam finite element method. This paper describes the second part of this model: simulating oil transport around the ring pack system (two compression rings and one twin-land oil control ring (TLOCR)) through the ring-liner interfaces by solving the oil film thickness on the liner. The ring dynamics model in Part 1 calculates the inter-ring gas pressure and the ring dynamic twist which are used in the ring-liner lubrication model as boundary conditions. Therefore, only in-plane conformability is calculated to obtain the oil film thickness on the liner. Both global process, namely, the structural response of the rings to bore distortion and piston tilt, and local processes, namely, bridging and oil-lube interaction, are considered. The model was applied to a passenger car engine.
2017-03-28
Technical Paper
2017-01-1626
Tomas Poloni, Jianbo Lu
Abstract This paper proposes a method to make diagnostic/prognostic judgment about the health of a tire, in term of its wear, using existing on-board sensor signals. The approach focuses on using an estimate of the effective rolling radius (ERR) for individual tires as one of the main diagnostic/prognostic means and it determines if a tire has significant wear and how long it can be safely driven before tire rotation or tire replacement are required. The ERR is determined from the combination of wheel speed sensor (WSS), Global Positioning sensor (GPS), the other motion sensor signals, together with the radius kinematic model of a rolling tire. The ERR estimation fits the relevant signals to a linear model and utilizes the relationship revealed in the magic formula tire model. The ERR can then be related to multiple sources of uncertainties such as the tire inflation pressure, tire loading changes, and tire wear.
2017-03-28
Journal Article
2017-01-1249
Masahiro Seguchi
Abstract Compact, high efficiency and high reliability are required for an xEV motor generator. IPM rotors with neodymium magnets are widely applied for xEV motors to achieve these requirements. However, neodymium magnet material has a big impact on motor cost and there is supply chain risk due to increased usage of these rare earth materials for future automotive xEV’s. On the other hand, a wound-field rotor does not need magnets and can achieve equivalent performance to an IPM rotor. However, brushes are required in order to supply current to the winding coil of the rotor. This may cause insulation issues on xEV motors which utilize high voltage and high currents. Therefore, it is suggested to develop a system which supplies electric energy to the rotor field winding coil from the stator without brushes by applying a transformer between stator coil and rotor field winding. Specifically, add auxiliary magnetic poles between each field winding pole and wind sub-coils to these poles.
2017-03-28
Journal Article
2017-01-0462
Marcel Meuwissen, Jippe Van Ruiten, Thijs Besseling, Robbert van Sluijs, Maik Broda, Brian Pearce, Fenton I. O'Shea
Abstract Fuel economy improvement efforts in engines have focused on reducing parasitic losses. This paper addresses the friction losses in the valve train chain drive system where about half of the losses is caused by the chain sliding on plastic guide and tensioner arm faces (Figure 1). Efforts have been made to reduce these friction losses by optimizing the chain link profile, the geometry of the guide and tensioner arm rails, and developments towards low friction materials. This paper describes the approach taken for the development of new low-friction chain tensioner arm plastic materials. The approach is characterized by building an understanding of the friction mechanisms and identifying the most critical material’s properties. A lab-scale test is used for a first assessment of the friction performance of materials. The correlation between this lab-scale test and the actual chain-on-tensioner arm application is discussed.
2017-01-10
Technical Paper
2017-26-0262
Neelakandan Kandasamy, Koundinya Narasimha Kota, Prasad Joshi
Abstract The structure of a vehicle is capable of absorbing a significant amount of heat when exposed to hot climate conditions. 50-70% of this heat penetrates through the glazing and raises both the internal cabin air temperature and the interior trim surface temperature. When driving away, the air conditioning system has to be capable of removing this heat in a timely manner, such that the occupant’s time to comfort will be achieved in an acceptable period [1]. When we reduce the amount of heat absorbed, the discomfort in the cabin can be reduced. A 1D/3D based integrated computational methodology is developed to evaluate the impact of vehicle orientation on cabin climate control system performance and human comfort in this paper. Additionally, effects of glazing material and blinds opening/closing are analyzed to access the occupant thermal comfort during initial and final time AC pull down test.
2017-01-10
Technical Paper
2017-26-0279
Onkar P Bhise, S Ravishankar
Abstract Polytetrafluoroethylene (PTFE) is used extensively as the inner tube material in various Aerospace and Industrial hose constructs. The fluoropolymer exhibits various unique mechanical properties from other fluoropolymers including chemical inertness, non-adhesiveness and low friction coefficient making it an attractive solution for hose applications. PTFE material can be modeled using various material modeling approaches including linear-elastic, hyperelastic and viscoplastic depending on the level of accuracy required in predicting material response. Fluoropolymers, like PTFE, are considered viscoelastic-viscoplastic materials. In other words, the material exhibits both viscous and elastic characteristics when undergoing deformation but also possesses behavior in which the deformation of the material also depends on the rate by which loads are applied.
2017-01-10
Technical Paper
2017-26-0310
Vyankatesh Madane, Sameer Shivalkar, Chandrakant Patil, Sanjeev Annigeri
Abstract In rubber industry, different techniques are used to enhance durability. This paper gives complete design, development and testing methodology of rubber bush in which pre-compression of rubber is used to enhance rubber bush life. In bogie suspension, axle to torque rod join is critical as it has to transfer lateral and longitudinal load with flexibility. This makes challenging to design joint which need to carry more than 6 ton load and having flexibility of more than 10 degree articulation. In this torque rod to axle joint called as End bush, compressed rubber is used to carry high load with flexibility. Other possible material for bush can be brass bush which able to carry high load however not able to give high flexibility Design and finite element calculations are done to design pre-compression and rubber volume to get desired strength and stiffness to carry required load with flexibility.
2017-01-10
Technical Paper
2017-26-0312
Sagar Polisetti, Ganeshan Reddy
Abstract Twist beam is a type of suspension system that is based on an H or C shaped member typically used as a rear suspension system in small and medium sized cars. The front of the H member is connected to the body through rubber bushings and the rear portion carries the stub axle assembly. Suspension systems are usually subjected to multi-axial loads in service viz. vertical, longitudinal and lateral in the descending order of magnitude. Lab tests primarily include the roll durability of the twist beam wherein both the trailing arms are in out of phase and a lateral load test. Other tests involve testing the twist beam at the vehicle level either in multi-channel road simulators or driving the vehicle on the test tracks. This is highly time consuming and requires a full vehicle and longer product development time. Limited information is available in the fatigue life comparison of multi-axial loading vs pure roll or lateral load tests.
2017-01-10
Technical Paper
2017-26-0167
Salah M. Khaleel, Bernard Rolfe, Riyadh Al-Ameri, Tim De Susa
Abstract Given the need to reduce mass in products to reduce emissions, particularly in the transportation sector, the application of adhesively bonded joints is becoming more utilised. This is very true for the emerging multi-material structures. The adhesive joint expresses good properties regarding stress distribution, sound isolation and fatigue resistance; these properties are well defined in many applications such as aircraft and car industry. However, the adhesive joints have some drawbacks in regard to the joint strength. One of the keys to strengthening joints is the surface treatment of the adherents. It is found that the surface treatments play an important role in improving the joint strength and durability. Moreover, it is also found that each adhesive material will require different types of surface treatments to make the right balance between the joint strength and fracture modes.
2017-01-10
Technical Paper
2017-26-0168
Ajeet Babu P K, Jibin Babu, M R Saraf
Abstract Forging is a metal forming process involving shaping of metal by the application of compressive forces using hammer or press. Forging load of equipment is an important function of forging process and the prediction of the same is essential for selection of appropriate equipment. In this study a hot forging material i.e. 42CrMo4 steel is selected which is used in automotive components like axle, crank shaft. Hot forging experiments at 750°C are carried out on cylindrical specimens of aspect ratio 0.75 and 1.5 with true height strain (ln (ho/hf)) of 0.6. Forging load for the experiments is calculated using slab and upper bound deformation models as well as Metal forming simulation using commercially available FEA software. The upper bound models with 30% deviation from the simulation results are found to be more accurate compared to the slab models.
2017-01-10
Technical Paper
2017-26-0169
K Chinnaraj, R Padmanaban
Abstract The objective of this paper is to provide a reliable and robust mechanics based analytical approach for the accurate prediction of residual stresses in cold formed steel members. The forming residual stresses and associated equivalent plastic strains in cold formed corner sections are predicted with the assumption of elastic-perfectly plastic material model. The predicted analytical solution results are then compared with the existing analytical solution results. This work demonstrates that the exact estimation of forming residual stresses and equivalent plastic strains are possible with the inclusion of shift in neutral axis resulting from unequal thresholds of plasticity levels at the top and bottom surfaces of small radius corner sections. The predicted forming residual stresses and the associated equivalent plastic strains together define the initial conditions of corner sections for further non-linear structural behavior analysis of cold formed structures.
2017-01-10
Technical Paper
2017-26-0170
Pratik Pillai, Sivakumar Venugopal, Vijaysankar Gopalan
This paper deals with the study of the phenomenon of crevice corrosion of aluminium by using an example of a corrosion failure of a joint in the automobile coolant circuit. A number of joint failures were studied to understand the corrosion pattern and for various metallurgical aspects like chemistry, hardness and microstructure. The corrosion products were analyzed using Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray Spectroscopy (EDS). This analysis indicated that the corrosion products mostly contained Aluminium Oxides with other contaminants like chlorides. The studies revealed that the clamped joint of the aluminium part and rubber hose led to the formation of a crevice with the engine coolant acting as the corrosive medium. The corrosion behavior at the location was affected by environmental factors like temperature, pH and chloride contamination.
2017-01-10
Technical Paper
2017-26-0175
Muhammad Ali Siddiqui, Hein Koelman, Prashant Sharad Shembekar
Abstract Composite manufacturing in the automotive industry is striving for short cycle times to be competitive with conventional manufacturing methods, while enabling significant weight reductions. High Pressure Resin Transfer Molding (HP-RTM) is becoming one of the processes of choice for composite applications due to its ability to enable high speed part production. In this regard, researchers need to offer differentiated ultra-fast curing resin systems for carbon fiber composites for automotive structural and nonstructural applications to enable Original Equipment Manufacturers (OEMs) to meet their large volume lightweight targets in concert with present day low-carbon footprint legislations. In order to expand applications for composites in the automotive industry it is necessary to optimize all aspects of the production cycle using predictive modeling.
2017-01-10
Technical Paper
2017-26-0181
Manish Vyas, Mark Pratley
Abstract There is an increased use of elastomers in the automotive industry for sealing, noise isolation, load dampening, insulation, etc., because of their key properties of elasticity and resilience. Elastomers are used in supercharger application for dampening the torsional fluctuation from the engine, to reduce noise issues. Finite element modeling of elastomers is challenging because of its non-linear behavior in different loading directions. It also undergoes very large elemental deformation (~up to 200%), which results in additional complexities in getting numerical convergence. Finally, it also exhibits viscous and elastic behavior simultaneously (viscoelastic effect) and it undergoes softening with progressive cyclic loading (Mullins effect). The present study deals with the characterization of elastomers for its modeling in commercial finite element software packages and verification of some predicted design parameters with physical testing.
2017-01-10
Technical Paper
2017-26-0195
Sachin Kumar Jain, Manasi Joshi, Harshal Bankar, Prashant Kamble, Prasad Yadav, Nagesh Karanth
Abstract The paper discusses the methodology for measuring the sound absorption of sound package materials in a different sizes of reverberation chambers. The large reverberation chamber is based on test methods and requirements as per ASTM C423 and ISO 354 standards. Both the test standards are similar and recommend a reverberation chamber volume of at least 125 m3 and 200 m3 respectively for sound absorption measurements from 100 Hz to 5000 Hz. The test sample size requirements are from 5.5 to 6.7 m2 as per ASTM C423 and 10 to 12 m2 as per ISO 354. In the automotive sector passenger car, heavy truck, and commercial vehicle, the parts that are used are much smaller in size than the size prescribed in both the standards. The requirement is to study the critical parameters such as the chamber volume, sample size, reverberation time and cut-off frequency etc. which are affecting the sound absorption property of acoustic material.
2017-01-10
Technical Paper
2017-26-0123
Fabien Ocampo, Naotaka Ohtake, Barry W. L. Southward
Abstract In order to achieve NOx tailpipe targets of current diesel regulation standards two main catalytic technologies have been employed, specifically NH3-SCR and LNT. However both of these technologies face challenges with the implementation of newer / colder test cycles such as “Real Driving Emissions” (RDE), combined with CO2 targets (95 g/km is 2020 target in Europe). These cycles will require higher NOx Storage Capacity (NSC) in the low temperature region (120-350°C). Conversely, lean-burn Gasoline vehicles, with their higher operational temperatures, will require improved NSC over a broader temperature range (200-500°C). Therefore, the development of NSC materials to meet these opposing requirements is an area of extensive study by Original Equipment Manufacturers (OEMs), washcoaters, and raw materials suppliers. Today, ceria is a key component in the formulation of active NSC washcoats.
2017-01-10
Technical Paper
2017-26-0052
Gopalakrishna Acharya, K.A. Subramanian, R K Malhotra
In India, there is a large population of heavy duty diesel engine powered vehicles such as trucks and buses. Buses are operated under normal speed & load conditions whereas trucks are generally overloaded with high severity on engine oil and lugging operation is common. Higher loading of soot in engine oil results in increase in viscosity of oil and also affects the friction properties and also wear in engine components. The engine oil keep the soot dispersed in order to meet the basic function of lubricating and also keep the engine components clean.
2017-01-10
Technical Paper
2017-26-0159
B Sakthivel, R Elayaraja, M Sivakumar, R Sridhar, J Suresh Kumar, B L Ganapati Subramaniyam
Abstract Solenoids are electro mechanical actuators used in automotive industries as flow control valve. Solenoids replace the conventional mechanical valve since it is having a precise control and faster response. Solenoid is operated either in ON/OFF mode or Pulse Width Modulation mode (PWM). When operated in PWM at a given frequency, the solenoid undergoes finite number of repeated operations. A normally closed solenoid contains two critical parts, one is a plunger, which is a moving part and another is valve case, which is a static part. The plunger hits the valve case during repeated number of operations which undergo extreme wear. Since the functionality and performance of the solenoid mainly rely on the plunger and valve case, it is inevitable to have an optimum material selection in order to achieve higher durability. This paper illustrates the study of material selection for an air control solenoid used for two wheeler application.
2017-01-10
Technical Paper
2017-26-0165
Meenu Srivastava, Umesh Kumar Sinha, M Muniprakash, A J Steve Mithran, K.M. Pillai
Abstract Automobile component particularly the engine cylinder is subjected to continuous wear during the running of the automobile specifically the two wheelers. Aluminium alloys are the material of choice due to their high strength/weight ratio. As aluminium alloys have poor wear and corrosion resistance, a uniform wear resistant composite coating is required on the bore of the internal combustion engine cylinder. There are several methods to produce composite coatings like chemical and physical vapour deposition, plasma spraying, metal infiltration, powder metallurgy etc. Ni-SiC coating commercially known as NIKASIL, is the most commercially used coating in automobile’s/aero IC engines. However, SiC tends to react with the nickel matrix at temperatures above 400 °C forming a brittle nickel silicide which deteriorates the performance of the coating. Also, the synthesis of SiC particles utilizes high energy.
2017-01-10
Technical Paper
2017-26-0157
Hari Prasad Konka, Anand Kumar Ramachandran, Shireesh Pankaj, Prasath Ganesan, Parimal Maity
Abstract Functionally graded materials enable structures to have distribution of different properties (physical, thermal, electrical, mechanical, etc.) across its volume; achievable via material/ design/ process engineering. These functionally graded materials can find an application in systems which demand localized variation or enhancement in properties in different regions of the same component. In this paper, we focus on the potential ways of designing functionally graded polymer composite structure by injection molding process. Advanced mold designs for injection molding process can be effectively used to manufacture the functionally graded structures. Innovative design approach has been explored to control the distribution of the filler content /orientation to impart distinctive properties across the cross section / geometry without affecting the bulk properties.
2017-01-10
Technical Paper
2017-26-0180
Swaminathan Ramaswamy, Christophe Schorsch, Mario Kolar
Abstract Automotive OEMs are adapting various “green” technologies to meet the upcoming and anticipated regulations for reducing direct and indirect GHG emissions equivalent to CO2. Using compact devices and lightweight components on the aggregates, OEMs get the benefit of carbon credits towards their contribution in reducing CO2 emissions. With regards to the HVAC systems, enhancements such as ultra-low permeation hose assemblies and adoption of low GWP refrigerant have shown promising results in reducing the direct GHG emissions by controlling refrigerant permeation & indirect GHG emissions by using compact and high efficiency compressors, compact heat exchangers, and other technologies that contribute to weight reduction and ultimately impact CO2 emissions. Traditional AC lines are routed/installed in space that accommodates the relative movement between the engine and chassis by connecting the various parts.
Viewing 271 to 300 of 15996