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Viewing 61 to 90 of 8953
2017-03-28
Technical Paper
2017-01-0308
Hyunok Kim, Jianhui Shang, James Dykeman, Anoop Samant, Clifford Hoschouer
Abstract Practical evaluation and accurate prediction of edge cracking are challenging issues in stamping AHSS for automotive body structures. This paper introduces a new hole-expansion testing method that could be more relevant to the edge cracking problem observed in stamping AHSS. A new testing method adopted a large hole diameter of 75 mm compared to the ISO standard hole diameter of 10 mm. A larger hole diameter was determined to be sensitive to edge cracking using the finite element method (FEM) based sensitivity analyses with various hole sizes. A die punching tool was developed to replicate typical production blanking conditions. An inline monitoring system was developed to visually monitor the hole edge cracking during the test and synchronize with the load-displacement data. Two AHSS materials, DP980 and TRIP780, and an aluminum alloy, A1 5182-O, were experimentally evaluated.
2017-03-28
Technical Paper
2017-01-0338
Jeong Kyun Hong, Andrew Cox
Abstract Even under uniaxial loading, seemingly simple welded joint types can develop multi-axial stress states, which must be considered when evaluating both the fatigue strength and failure location. Based on the investigation of fatigue behavior for the multi-axial stress state, a procedure for fatigue behavior of welded joints with multi-axial stress states was proposed using an effective equivalent structural stress range parameter combined normal and in-plane shear equivalent structural stress ranges and the master S-N curve approach. In automotive structures, fatigue failure is often observed at weld end, which often show a complex stress state. Due to simplified weld end representation having a sharp right-angled weld corner, the fatigue failure prediction at the weld end tends to be overly conservative due to the excessive stress concentration at the right-angled weld termination.
2017-03-28
Technical Paper
2017-01-0474
Chady Khalil, Yannick Amosse, Guillaume Racineux
Abstract In this study, a proposed new 3-in-1 process using the magnetic pulse welding (MPW) for welding similar and dissimilar metals and for hybrid joining between FRC and metals is developed. Welding between (a) AA1199 sheets and XES, (b) AA1199 and XSG which is zinc coated steel, (c) 5754-aluminum alloy and XES were performed and (d) hybrid joint between PA66-glass-FRC and 5754-aluminum was achieved. SEM observations and EDX analysis for the weld interface between aluminum and steel showed where detectable very thin layers of intermetallics and the wavy interface pattern typical for impact welding was identified. X-Ray microtomography observation for the joining region in the FRC showed the good state of the composite structure after joining. 3D numerical simulation using LS-Dyna was used for the selection of the welding parameters. Quasi-static lap shear testing for the welds revealed a failure in the weak metal sheet and not in the weld.
2017-03-28
Technical Paper
2017-01-0476
Seiji Furusako, Masatoshi Tokunaga, Masanori Yasuyama
Abstract To reduce the weight of automobile bodies, application of high-strength steel sheets is expanding. Furthermore, middle and high carbon steels are expected to be used to lower the environmental impact and cost in the automobile steel sheet industry. However, it is necessary to enhance the joint strength of the steel sheets. In this study, hat-shaped components were made using resistance spot (RS) welding or arc spot (AS) welding on S45C steel sheets (including 0.44% carbon), 1.4 mm thickness and strength of 1180 MPa grade. A dynamic three-point bending test was conducted on the components and their crashworthiness was compared. Some RS welds fractured (separated) during the three-point bending test even though the diameter of the weld metal was increased to 5√t (t means thickness of the sheet); however, AS welds did not fracture.
2017-03-28
Technical Paper
2017-01-0467
Wei Yuan, Brian Jordon, Bita Ghaffari, Harish Rao, Shengyi Li, Min Fan
Abstract Lightweight metals such as Al and Mg alloys have been increasingly used for reducing mass in both structural and non-structural applications in transportation industries. Joining these lightweight materials using traditional fusion welding techniques is a critical challenge for achieving optimum mechanical performance, due to degradation of the constituent materials properties during the process. Friction stir welding (FSW), a solid-state joining technique, has emerged as a promising method for joining these lightweight materials. In particular, high joining efficiency has been achieved for FSW of various Al alloys and Mg alloys separately. Recent work on FSW of dissimilar lightweight materials also show encouraging results based on quasi-static shear performance. However, coach-peel performance of such joints has not been sufficiently examined.
2017-03-28
Technical Paper
2017-01-0471
Yasuo Kadoya, Yuki Oshino
Abstract By implementation of the core technology of capacitor-resistance welding, RingMash technology, metallic bonding, is developed to manufacture various components. It is the best suited for powertrain components such as transmission gears at low cost. Components made by RingMash are attributed to smaller and lighter transmission. The technology is recommended to manufacture co-axle male-female work pieces bonding, male side diameter is slightly larger than female side hole. RingMashing is a solid state bonding without melting work pieces. The actual RingMashing process is done in ambient atmosphere and does not use filler. RingMashing process itself takes only 100 milliseconds, results very minimum Heat-Affected Zone (HAZ), normally no more than 1 mm. The minimum HAZ achieves excellent structural integration for better performance of transmission. If two work pieces are same metals, spattering free bonding is possible.
2017-03-28
Technical Paper
2017-01-1726
Sameer Shah, Aayoush Sharma, Raghav Angra, Nitin Singh, Khalique Ahmed
Abstract In an unavoidable event of a suspect being chased by police, there is high probability for the criminal to evade the police while driving his vehicle. At many instances, criminal escapes without leaving a trail behind and becomes untraceable. A new concept of Vigilance Assistance System Network (VASN) has been developed, which is spread across the city and helps in catching the escaping criminals. At every junction, the traffic-signals are installed with a microcontroller chip and these connected traffic signals form a network with distinct city areas demarcated on the map. The vehicle is installed with GPS and a RFID module on their ECU when it approaches any intersection or junction; they receive wireless signals from traffic-signals and transmit another registering signal to the traffic-light wirelessly through RFID.
2017-03-28
Technical Paper
2017-01-1732
Payodh Dwivedi
Abstract The conventional hybrid engine faces one major problem i.e. high cost of production. Although hybrid engines, in many sense proved to be highly efficient and environmental friendly, but high cost of production makes them less feasible and limits their applications. This problem is overcome by a new design in which instead of having Internal Combustion(IC) engine and electric motor separately, these two are incorporated under same housing. This involves a different working mechanism of electric motor which is as described below- This mechanism is applied to a normal engine which has two or more than two cylinders in any configuration or orientation. Taking example of In-line four cylinder engines as it is most widely used. In this the two cylinders work on conventional internal combustion mechanism, but the other two cylinders are electric cylinder and works on electricity.
2017-03-28
Technical Paper
2017-01-1275
David Hobbs, Charles Ossenkop, Andy Latham
Abstract Global sales of electric and hybrid vehicles continue to grow as emission legislation forces vehicle manufacturers to build cleaner vehicles, with some 8 million already in service. Hybrid and Electric vehicles contain some of the most complex systems ever used in the automotive field, sophisticated and unique electric hybrid systems are added to modern motor vehicles which are already quite complex. As these vehicles reach the end of their lives they will be processed by the global vehicle recycling industry and the high voltage components will be reused, recycled or re-purposed. This paper explores safe working practices for businesses involved in a global marketplace who are completing battery disabling, removal, disassembly, storage and shipping; includes the various technologies and safe working practices along with some of the legal restrictions on dismantling, storage and shipping of high voltage batteries around the world.
2017-03-28
Technical Paper
2017-01-1529
Nicholas Simmonds, John Pitman, Panagiotis Tsoutsanis, Karl Jenkins, Adrian Gaylard, Wilko Jansen
Abstract Cooling drag, typically known as the difference in drag coefficient between open and closed cooling configurations, has traditionally proven to be a difficult flow phenomenon to predict using computational fluid dynamics. It was seen as an academic yardstick before the advent of grille shutter systems. However, their introduction has increased the need to accurately predict the drag of a vehicle in a variety of different cooling configurations during vehicle development. This currently represents one of the greatest predictive challenges to the automotive industry due to being the net effect of many flow field changes around the vehicle. A comprehensive study is presented in the paper to discuss the notion of defining cooling drag as a number and to explore its effect on three automotive models with different cooling drag deltas using the commercial CFD solvers; STARCCM+ and Exa PowerFLOW.
2017-03-28
Journal Article
2017-01-0266
Shervin Shoai Naini, Junkui (Allen) Huang, Richard Miller, John R. Wagner, Denise Rizzo, Scott Shurin, Katherine Sebeck
Designing an efficient cooling system with low power consumption is of high interest in the automotive engineering community. Heat generated due to the propulsion system and the on-board electronics in ground vehicles must be dissipated to avoid exceeding component temperature limits. In addition, proper thermal management will offer improved system durability and efficiency while providing a flexible, modular, and reduced weight structure. Traditional cooling systems are effective but they typically require high energy consumption which provides motivation for a paradigm shift. This study will examine the integration of passive heat rejection pathways in ground vehicle cooling systems using a “thermal bus”. Potential solutions include heat pipes and composite fibers with high thermal properties and light weight properties to move heat from the source to ambient surroundings.
2017-03-28
Technical Paper
2017-01-1225
Jayaraman Krishnasamy, Martin Hosek
Abstract An advanced electric motor with hybrid-field topology has been developed for automotive traction applications. Departing from the conventional radial- and axial-field designs, the hybrid-field motor features three-dimensional magnetic flux paths, which are enabled by a novel isotropic soft magnetic material produced by a unique additive-manufacturing process based on spray forming. The motor is expected to offer an unprecedented combination of high power output, compact size, low weight and energy efficiency, achieving more than two times higher power density than state-of-the-art high-performance traction motors.
2017-03-28
Journal Article
2017-01-0288
Hai Wu, Meng-Feng Li
Abstract The human-robot interaction (HRI) is involved in a lift assistant system of manufacturing assembly line. The admittance model is applied to control the end effector motion by sensing intention from force of applied by a human operator. The variable admittance including virtual damping and virtual mass can improve the performance of the systems. But the tuning process of variable admittance is un-convenient and challenging part during the real test for designers, while the offline simulation is lack of learning process and interaction with human operator. In this paper, the Iterative learning algorithm is proposed to emulate the human learning process and facilitate the variable admittance control design. The relationship between manipulate force and object moving speed is demonstrated from simulation data. The effectiveness of the approach is verified by comparing the simulation results between two admittance control strategies.
2017-03-28
Journal Article
2017-01-0290
Veera Aditya Yerra, Srikanth Pilla
Abstract The advancements in automation, big data computing and high bandwidth networking has expedited the realization of Industrial Internet of Things (IIoT). IIoT has made inroads into many sectors including automotive, semiconductors, electronics, etc. Particularly, it has created numerous opportunities in the automotive manufacturing sector to realize the new aura of platform concepts such as smart material flow control. This paper provides a thought provoking application of IIoT in automotive composites body shop. By creating a digital twin for every physical part, we no longer need to adhere to the conventional manufacturing processes and layouts, thus opening up new opportunities in terms of equipment and space utilization. The century-old philosophy of the assembly line might not be the best layout for vehicle manufacturing, thus proposing a novel assembly grid layout inspired from a colony of ants working to accomplish a common goal.
2017-03-28
Journal Article
2017-01-0293
Tina Hull
Abstract Recent advances in technology allow machine safeguarding to shift from a system that completely shuts down the hazardous part of a machine, regardless of the action, to one with a controlled response. This intelligent robotics safeguarding can be based on conditions such as the type of task, how it is performed, entry and exit locations, and the operator’s movement within the hazard zone. Such a strategy could increase production rates by allowing robots to operate at higher speeds within dynamic environments. When used as part of a preventative maintenance program, reliability data can predict component failure rates and reduce the probability that operators will access the hazard zone. Programming techniques, such as function blocks to monitor component usage, can be used to evaluate trends. SQL (Structured Query Language) databases can track access and frequency trends, which can lead to design improvements and indicate changes affecting the system.
2017-03-28
Journal Article
2017-01-0298
Allen Dobryden, Brian Rutter, Derek Hartl, Eric Bramson
Abstract Adoption of new technology with ever increasing complexity challenges organizational structures and processes as subsystem ownership crosses several powertrain subsystem boundaries (and thereby involves multiple departments). Integrating such technology without introducing inadvertent failure modes can be a difficult task. This paper illustrates an upfront approach to understanding the potential system impact of using an example new technology. In product development activities involving primarily reuse of known technologies, organizational and subsystem boundaries are generally clear. Interfaces are well established and responsibilities for managing failure mode avoidance are generally known. Implementation of new technology which does not naturally fit the well-established organizational definitions and boundaries presents distinctive challenges to system design, system integration, and verification using failure mode avoidance (FMA).
2017-03-28
Journal Article
2017-01-0299
Chandra Jalluri, Himanshu Rajoria, Mark Goderis, Michael Habel, Trevor Hill
Abstract Thermal growth of spindle and other components is common in CNC machines, especially with MQL machining, and directly impacts positioning accuracy and thereby quality. A common method to address this is by measuring the thermal growth using gage bore probing and then compensating for it. Application of this method in 5-axis CNC machines is relatively new and effectiveness is often not tested. Error sources due to various orientations of the part could arise. A new artifact based method is presented for assessment of thermal compensation used by the CNC OEM. The method involves an artifact, test cycle and automated data logging. A precision granite artifact with gage bores on different faces is fabricated and can be presented for probing in different orientations. The machine is warmed up using repeated dry-cycling, thereby creating thermal growth. Compensation error is evaluated as the difference of actual thermal growth and compensation offset.
2017-03-28
Journal Article
2017-01-0302
Saeid Nasheralahkami, Sergey Golovashchenko, Scott Dawson, Raj Sohmshetty
Abstract In recent years, implementation of dual phase (DP) Advanced High Strength Steels (AHSS) and Ultra High Strength Steels (UHSS) is increasing in automotive components due to their superior structural performance and vehicle weight reduction capabilities. However, these materials are often sensitive to trimmed edge cracking if stretching along sheared edge occurs in such processes as stretch flanging. Tool wear is another major issue in the trimming of UHSS because of higher contact pressures at the interface between cutting tools and sheet metal blank caused by UHSS’s higher flow stresses and the presence of a hard martensitic in the microstructure. The objective of the present paper is to discuss the methodology of analyzing die wear for trimming operations of UHSS components and illustrate it with some examples of tool wear analysis for trimming 1.5mm thick DP980 steel.
2017-03-28
Journal Article
2017-01-0303
Ran Cai, Xueyuan Nie, Jingzeng Zhang
Abstract Light-weighting of vehicles is one of the challenges for transportation industry due to the increasing pressure of demands in better fuel economy and environment protection. Advanced high strength steels (AHSS) are considered as prominent material of choice to realize lightweight auto body and structures at least in near term. Stamping of AHSS with conventional die materials and surface coatings, however, results in frequent die failures and undesired panel surface finish. A chromium nitride (CrN) coating with plasma nitriding case hardened layer on a die material (duplex treatment) is found to offer good wear and galling resistances. The coating failure initiates from fatigue cracking on the coating surface due to cyclic sliding frictions. In this work, cyclic inclined sliding wear test was used to imitate a stamping process for study on development of coating fatigue cracking, including crack length and spacing vs. sliding-cycles and sliding energy densities.
2017-03-28
Journal Article
2017-01-0306
Brandon M. Hance
Abstract Until now the hole expansion ratio has been generally regarded as a relative “local formability” parameter with limited application to edge-cracking analysis and prediction. In this study a constrained statistical test data analysis methodology is introduced, where the lower-bound hole expansion ratio is the basis for three practical edge-cracking failure criteria. The Maximum Edge Stretch Criterion is directly compatible with CAE simulation. The Edge Thinning Limit Criterion and the Critical Thickness Criterion are more useful in field work and post mortem laboratory failure analysis. Two case studies are described, where hole expansion test data are used to analyze edge cracking of Advanced High Strength Steel (AHSS) in real-world automotive seating applications.
2017-03-28
Journal Article
2017-01-0310
Wei Wu, Dajun Zhou, Donald Adamski, Darryl Young, Yu-Wei Wang
Abstract The die wear up to 80,800 hits on a prog-die setup for bare DP1180 steel was investigated in real production condition. In total, 31 die inserts with the combination of 11 die materials and 9 coatings were evaluated. The analytical results of die service life for each insert were provided by examining the evolution of surface wear on inserts and formed parts. The moments of appearance of die defects, propagation of die defects, and catastrophic failure were determined. Moreover, the surface roughness of the formed parts for each die insert was characterized using Wyko NT110 machine. The objectives of the current study are to evaluate the die durability of various tooling materials and coatings for flange operations on bare DP 1180 steel and update OEM tooling standards based on the experimental results. The current study provides the guidance for the die material and coating selections in large volume production for next generation AHSSs.
2017-03-28
Journal Article
2017-01-0315
Yueqian Jia, Yangyang Qiao, Hao Pan, Edmund Chu, Yuanli Bai
Abstract A comprehensive plasticity and fracture model was built for metal sheets with application to metal sheet forming and vehicle crash simulations. The combined Bai-Wierzbicki (BW [1]) and CPB06ex2 [2] (or Yld2000-2D [3]) anisotropic plasticity model was further extended to consider elevated temperature effects in additional to the effect of multiaxial stress states. A fully modularized framework was established to combine isotropic, kinematic, and cross hardening behaviors under non-linear loading conditions. The all strain based modified Mohr-Coulomb (eMMC) fracture model was used to consider material anisotropy and nonlinear strain path. The model has been implemented into Abaqus/Explicit as a user material subroutine (VUMAT). Test results on advanced high strength steels, aluminum alloy sheets and magnesium alloy sheets are used to validate the modeling and testing methodologies. Very good correlation was observed between experimental and simulation results.
2017-03-28
Journal Article
2017-01-0342
Benjamin Möller, Alessio Tomasella, Rainer Wagener, Tobias Melz
Abstract The cyclic material behavior is investigated, by strain-controlled testing, of 8 mm thick sheet metal specimens and butt joints, manufactured by manual gas metal arc welding (GMAW). The materials used in this investigation are the high-strength structural steels S960QL, S960M and S1100QL. Trilinear strain-life curves and cyclic stress-strain curves have been derived for the base material and the as-welded state of each steel grade. Due to the cyclic softening in combination with a high load level at the initial load cycle, the cyclic stress-strain curve cannot be applied directly for a fatigue assessment of welded structures. Therefore, the transient effects have been analyzed in order to describe the time-variant material behavior in a more detailed manner. This should be the basis for the enhancement of the fatigue life estimation.
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
2017-01-0625
Yen-Chung Liu, Brian Sangeorzan, Alex Alkidas
Abstract The purpose of this research was to measure and correlate the area-average heat transfer coefficients for free, circular upward-impinging oil-jets onto two automotive pistons having different undercrown shapes and different diameters. For the piston heat transfer studies, two empirical area-average Nusselt number correlations were developed. One was based on the whole piston undercrown surface area with the Nusselt number based on the nozzle diameter, and the other was based on the oil-jet impingement area with the Nusselt number based on the oil-jet effective impingement diameter. The correlations can predict the 95% and 94% of the experimental measurements within 30% error, respectively. The first correlation is simpler to use and can be employed for cases in which the oil jet wets the whole piston undercrown. The latter may be more useful for larger pistons or higher Prandtl number conditions in which the oil jet wets only a portion of the undercrown.
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
2017-01-1705
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
2017-01-1642
Don Price
Abstract The force required to assemble automotive electrical connectors has been tested using a range of mating speeds in a controlled lab environment. This set of tests answers questions often brought up regarding how mating speed significantly influences the required applied force. Data from these evaluations show small but consistent mate force changes with assembly speed. Sealed and unsealed connectors were found to respond differently to mating speed, which is explained using a theoretical analysis. The mechanical analysis explains what forces are involved and how they are influenced by speed. Practical recommendations are given on how mate force testing should be done to assure results are as useful as possible. Results show that that mating speed has a positive correlation to peak mate force. An opposite, negative, correlation for unsealed connectors was found.
2017-03-28
Journal Article
2017-01-1201
Zhenli Zhang, Zhihong Jin, Perry Wyatt
Abstract Lithium plating is an important failure factor for lithium ion battery with carbon-based anodes and therefore preventing lithium plating has been a critical consideration in designs of lithium ion battery and battery management system. The challenges are: How to determine the charging current limits which may vary with temperature, state of charge, state of health, and battery operations? Where are the optimization rooms in battery design and management system without raising plating risks? Due to the complex nature of lithium plating dynamics it is hard to detect and measure the plating by any of experimental means. In this work we developed an electrochemical model that explicitly includes lithium plating reaction. It enables both determination of plating onset and quantification of plated lithium. We have studied the effects of charging pulses on homogenous plating in order to provide guidance for lithium ion battery design in hybrid applications.
2017-03-28
Journal Article
2017-01-0229
Hongyi Xu, Yang Li, Danielle Zeng
Abstract Process integration and optimization is the key enabler of the Integrated Computational Materials Engineering (ICME) of carbon fiber composites. In this work, automated workflows are developed for two types of composites: Sheet Molding Compounds (SMC) short fiber composites, and multi-layer unidirectional (UD) composites. For SMC, the proposed workflow integrates material processing simulation, microstructure representation volume element (RVE) models, material property prediction and structure preformation simulation to enable multiscale, multidisciplinary analysis and design. Processing parameters, microstructure parameters and vehicle subframe geometry parameters are defined as the design variables; the stiffness and weight of the structure are defined as the responses. For multi-layer UD structure, this work focuses on the discussion of different design representation methods and their impacts on the optimization performance.
Viewing 61 to 90 of 8953