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Viewing 61 to 90 of 20990
2017-03-28
Technical Paper
2017-01-0340
Li Lu, Jeffrey Webb, Jane Zhou, Derren Woods, Thomas Pietila, Ram Iyer
Injection molding tools are expensive and the fatigue failure during production would result in very costly rework on tool and downtime. Currently mold designs are mostly based on expert experience without a careful stress analysis and the mold set life cycle relies largely on a rough estimates. There are three major causes of mold damage: 1) Thermal stress due to rapid heating and cooling (thermal shock); 2) Mold deflection due to injection pressure imbalance; 3) Clamping force induced stress inside mold blocks. The industry state of the art applies averaged temperature change and peak pressure load on the mold tool and static analysis is performed. Mold temperature history and thermal shock are not considered in the durability analysis. In the developed integrated CAE tool, a transient thermal analysis of the tool is performed in conjunction with the injection molding process simulation.
2017-03-28
Technical Paper
2017-01-1321
Meisam Mehravaran, Yi Zhang
Degas Bottles have been extensively used in vehicles in order to act as an air pillow on top of the cooling loop and provide space for expansion. One of the important characteristics of the bottle which defines if it will work in a certain loop is the so called “capacity” of the bottle which defines the flowrate that degas bottle would be able to pass through without any foaming. Considering the complex geometry of degas bottle and the foaming phenomena, predicting the behavior of coolant in the bottle passages is challenging which requires costly tests. Computational Fluid Dynamics (CFD) has been extensively used in simulating multi-phase flows in automotive components. In the current project, CFD has been used to simulate the behavior of flow in bottle chambers and to provide guidelines for the design team in order to increase the bottle performance/capacity. The CFD guidelines were in agreement with test results and lead to improving the degas bottle capacity.
2017-03-28
Technical Paper
2017-01-0396
Guobiao Yang, Changqing Du, Dajun Zhou, Hao Wang, Elizabeth Lekarczyk, Lianxiang Yang
As we know, the lighting car is very important for automotive industry in recent years. There are lot of components which could be lighted weight in one vehicles. In modern automotive field Aluminum alloy widely has been used to formed into parts of vehicles, because it has very good ideal properties for the stamping process which need material both malleable and ductile. During vehicles manufacture process, lots of aluminum alloy has been stamped into parts of components. It is very important for engineer to know how to predict the fracture of aluminum alloy, in order to simulate stamping process in automotive field by FEM. This research presents strains distribution of A5182 aluminum during sample being impacted with punch heads under loading. DIC has been used technically to measure the whole history strain when sheet sample has been impacted, and the shape of sheet sample also has been tested in order to obtain the aluminum sheet springback(side-wall-curl).
2017-03-28
Technical Paper
2017-01-0223
Haolong Liu, Weidong Wen, Xuming Su, Carlos Engler-Pinto, HongTae Kang
Morphological features of voids were characterized for T300/924 12-ply and 16-ply composite laminates at different porosity levels through the implementation of a digital microscopy (DM) image analysis technique. The composite laminates were fabricated through compression molding. Compression pressures of 0.1MPa, 0.3MPa, and 0.5MPa were selected to obtain composite plaques at different porosity levels. Tension-tension fatigue tests at load ratio R=0.1 for composite laminates at different void levels were conducted, and the dynamic stiffness degradation during the tests was monitored. Fatigue mechanisms were then discussed based on scanning electron microscope (SEM) images of the fatigue fracture surfaces. The test results showed that the presence of voids in the matrix has detrimental effects on the fatigue resistance of the material, depending on the applied load level.
2017-03-28
Technical Paper
2017-01-0308
Hyunok Kim, Jianhui Shang, James Dykeman, Anoop Samant, Clifford Hoschouer
Practical evaluation and accurate prediction of edge cracking are very 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 and used to obtain consistent sheared-edge quality. 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 (i.e. DP980 and TRIP780) and an aluminum alloy, A1 5182-O were experimentally evaluated.
2017-03-28
Technical Paper
2017-01-0309
Mitchell Rencheck, Paul Zelenak, Jianhui Shang, Hyunok Kim
Aluminum alloys are increasingly utilized in automotive body panels and crash components to reduce weight. Accurately assessing formability of the sheet metal can reduce design iteration and tooling tryouts to obtain the desired geometry in aluminum stampings. The current ISO forming limit curve (FLC) procedure is a position dependent technique which produces the FLC based on extrapolation at the crack location. As aluminum sheet metal use increases in manufacturing, accurate determination of the forming limits of this material will be a necessity prior to production. New time dependent methods using digital imaging correlation (DIC) account for variations in deformation behavior by continuously collecting strain data through the material necking point. This allows more accurate FLC determination that is necessary for efficient design in the automotive stamping industry.
2017-03-28
Technical Paper
2017-01-0293
Tina Hull
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. It can be based on conditions such as the type of task, how it is performed, entry and exit locations, and operator movement within the hazard zone. A variety of options are available using existing principles with enhanced safety features. Component reliability data is used to calculate predicted failure rates. When it is used as part of a preventative maintenance program to replace components before they fail, it becomes a tool to reduce the probability of operators requiring increased future access into the hazard zone. Programming techniques such as function block to monitor component usage can be used to track actual system use and adjust reliability calculations.
2017-03-28
Technical Paper
2017-01-0394
Junrui Li, Ruiyan Yang, Zhen Li, Changqing Du, Dajun Zhou, Lianxiang Yang
Advanced high-strength steel (AHSS) is gaining popularity in the automotive industry due to its higher final part strength with the better formability compares to the conventional steel. However, the edge fracture occurs during the forming procedure for the pre-strained part. To avoid the edge fracture happens during the manufacturing, the effect of pre-strain on edge cracking limit need to be studied. In this paper, digital image correlation (DIC), as a high accuracy optical method, is adopted in the strain measurement for the edge cracking limit determination. Sets of the wide coupons are pre-strained to obtain the samples at different pre-strain level. The pre-strain of each sample is precisely measured during this procedure using DIC. After pre-straining, the half dog bone samples are cut from these wide coupons. The edge of the notch in the half dog bone samples is created by different methods for the distinct edge condition.
2017-03-28
Technical Paper
2017-01-0506
Xueyuan Nie, Jimi Tjong
Ultra-high strength steel (UHSS) and magnesium (Mg) alloy have found their importance in response to automotive strategy of light weighting. UHSS to be metal-formed by hot stamping usually has a hot-dipped aluminum-silicon alloy layer on its surface to prevent the high temperature scaling during the hot stamping and corrosion during applications. In this paper, a plasma electrolytic oxidation (PEO) process was used to produce ceramic oxide coatings on aluminized UHSS and Mg with intention to further improve their corrosion resistances. A potentiodynamic polarization corrosion test was employed to evaluate general corrosion properties of the individual alloys. Galvanic corrosion of the aluminized UHSS and magnesium alloy coupling with and without PEO coatings was studied by a zero resistance ammeter (ZRA) test. It was found that the heating-cooling process simulating the hot stamping would reduce anti-corrosion properties of aluminized UHSS due to the outward iron diffusion.
2017-03-28
Technical Paper
2017-01-0471
Yasuo Kadoya, Yuki Oshino
By implementation of core technology of Capacitor-resistance welding, RingMash technology, metallic bonding, is developed to manufacture svarious components, 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 piece. The actual RingMashing process is done in ambient atmosphere and does not use filler. RingMashing bonding 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, sputtering free bonding is possible.
2017-03-28
Technical Paper
2017-01-0481
Xian Jun sun, Patricia Tibbenham, Jin Zhou, Danielle Zeng, Shiyao Huang, Li Lu, Xuming Su
It is important to investigate on the weld line of injection molded part because the weld line area could induce potential failure for structural application. In this paper, the weld line factor(W-L factor) was adopted to describe the strength reduction to the bulk strength due to the appearance of weld line. There were five engineering thermoplastics involved in this study, including neat PP, talc filled PP, TPO, ABS and PC/ABS. The experimental design was used to investigate on four main injection molding parameters (melt temperature, mold temperature, injection speed and packing pressure). Both the bulk and weld line samples were prepared at each process settings. The sample strength was obtained by the tensile tests under two levels of testing speeds(5mm/min and 200mm/min) and testing temperatures(room temperature and -30oC). The results showed that different materials had various W-L factors. For neat PP, the W-L factor was highest and independent to injection mold parameters.
2017-03-28
Technical Paper
2017-01-0224
Zhangxing Chen, Yi Li, Yimin Shao, Tianyu Huang, Hongyi Xu, Yang Li, Wei Chen, Danielle Zeng, Katherine Avery, HongTae Kang, Xuming Su
Due to the increasing demand for vehicle light-weighting, chopped carbon fiber SMC(Sheet molding compound) as a promising material has attracted a lot of attentions. However, there exist few open data and researches on the property of this material as well as lack the method to predict the property. For these reasons, an RVE model for chopped carbon fiber SMC is proposed to predicting the material property.Voroni method are used to create the RVE model and fiber orientation tensor and fiber tow information for the RVE model are extracted from the different layer of material images.DIC test is also conducted to obtain the modulus of the materials.And the results of the RVE are filled into a tensile bar FEA model to compare with the experimental results,Great consistency can be seen between the model and experimental results which mean the proposed model can be used as a way to predict the property of this material.
2017-03-28
Technical Paper
2017-01-0231
Shih-Po Lin, Yijung Chen, Danielle Zeng, Xuming Su
In the conventional approach, the material properties of laminate composites for crash simulations are typically obtained from standard coupon tests, where the test results only provide single layer material properties. However, the lay-up effects for the failure behaviors of the real structure were not considered in numerical simulations. Hence, there was discrepancy between the crash simulations and experimental tests. Consequently, an intermediate stage is required for accurate predictions. Some component tests are required to calibrate the material models in the intermediate stage. In this paper, a laminate cylinder tube under high-impact velocity in the direction of tube axis is chosen as an example for the crash analysis. The tube consists of 24 layers of uni-directional (UD) carbon fiber composite materials, in which 4 layers are perpendicular to, while the other layers are parallel to the impact direction.
2017-03-28
Technical Paper
2017-01-1372
Bo Wang, Smruti Panigrahi, Mayur Narsude, Amit Mohanty
Increasing numbers of vehicles are equipped with telematics devices and they are able to transmit vehicle CAN bus information remotely. We examine the possibility of identifying individual drivers from their on-road driving behaviors. This study collected vehicle telematics data from a small fleet of Ford Fiesta vehicles over 6 months in London, UK. The collected variables included vehicle speed, acceleration pedal position, brake pedal pressure, steering angle position, gear position, and engine RPM. A list of driving metrics were developed to quantify driver behaviors, such as mean brake pedal pressure and turning speed. The Random Forest (RF) machine learning algorithm is used to predict driver IDs based on the developed driving metrics. The RF model is also used to rank the importance of each driving metric on driver identification. In conclusion, this paper demonstrates the possibility of identifying drivers from their on-road driving behaviors.
2017-03-28
Technical Paper
2017-01-1709
Zhigang Wei, Sarat Das, Ryan Barr, Greg Rohrs, Robert Rebandt, Xiao Wu, HongTae Kang
Recent stringent government regulations on emission control and fuel economy drive the vehicles and their associated components and systems to the direction of lighter weight. However, the achieved lightweight must not be obtained by sacrificing other important performance requirements such as manufacturability, strength, durability, reliability, safety, noise, vibration and harshness (NVH). Additionally, cost is always a dominating factor in the lightweight design of automotive products. Therefore, a successful lightweight design can only be accomplished by better understanding the performance requirements, the potentials and limitations of the designed products, and by balancing many conflicting design parameters. The combined knowledge-based design optimization procedures and, inevitably, some trial-and-error design iterations are the practical approaches that should be adopted in the lightweight design for the automotive applications.
2017-03-28
Technical Paper
2017-01-1275
David Hobbs, Charles Ossenkop, Andy Latham
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 re 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
2017-01-0474
Chady Khalil, Yannick Amosse, Guillaume Racineux
The use of dissimilar materials in the aim of reducing vehicles weight is increasing in the automotive industry and therefore joining between different types of materials became a priority especially between aluminum and steel as well as between metals and fiber-reinforced composites. The presented work will discuss a solution developed by Ecole Centrale de Nantes in collaboration with FAURECIA Group for welding aluminum to steel (and galvanized steel) using the magnetic pulse spot welding (MPSW) as well as a new patented process for hybrid joining of metals to fiber-reinforced composites based on the MPSW. In both cases, the explanation of the principle will be found first to go after that through the experimental applications achieved to study the process feasibility where the strength of the joining in both cases was tested and presented good results.
2017-03-28
Technical Paper
2017-01-0303
Ran Cai, Xueyuan Nie, Jingzeng Zhang
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
Technical Paper
2017-01-0400
Theo Rickert
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. The orbiting motion affects the hole shape since the drilling tool cannot make a truly flat bottom unless the tool edges reach each part of the bottom, i.e. if the holes radius is twice the tool diameter. For instance, square-end end mills leave an inverted cone on the hole bottom, which has a systematic effect on the near-surface stresses unless the coefficients account for the non-cylindrical hole shape. This paper compares measurements made with tools of several sizes and different orbiting offsets and discusses the systematic effects found.
2017-03-28
Technical Paper
2017-01-0229
Hongyi Xu, Yang Li, Danielle Zeng
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.
2017-03-28
Technical Paper
2017-01-0452
David A. Stephenson
Thermally sprayed engine bores require surface preparation prior to coating to ensure adequate adhesion. Mechanical roughening methods, in which a fine-scale dovetail profile is cut into the bore wall, produce surfaces which are easily gaged and are attractive for high volume. The currently available mechanical roughening methods are finish-boring based processes in which a standard boring insert is replaced with a PCD insert in which the roughening profile has been cut by EDM. These methods require diameter-specific tooling and significant clearance at the bottom of the bore for tool overtravel and retraction. This paper describes a new mechanical roughening method based on circular interpolation rather on finish boring. This method uses two tools: a side cutting end mill with peripheral grooves, which cuts a series of concentric grooves in the bore wall through interpolation, and a rotary swage which deforms the grooves to produce an undercut.
2017-03-28
Technical Paper
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 peak component heat loads. 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
2017-01-1201
Zhenli Zhang, Zhihong Jin, Perry Wyatt
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 plating. 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
Technical Paper
2017-01-1642
Don Price
Each of the 300 (or more) electrical connectors in a vehicle is assembled by hand. Since there is a risk of a repetitive stress injury resulting from any of these connectors, significant work has been done to determine what test needs to be performed to determine whether a connector is ergonomically safe for the person performing the assembly operation. This prior work has determined the maximum force that can be safely applied to mate a connector... what is not known is whether the mate force of a connector is influenced by the assembly speed on connector. This has significant practical interest since the preferred lab-based test speed is 50mm/min., which is ten times slower than the typical assembly speed in a vehicle assembly plant. There have been some calls for a change in the current testing method to use speeds that match typical assembly speeds.
2017-03-28
Technical Paper
2017-01-0290
Veera Aditya yerra, Srikanth Pilla
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 polylemma of production technologies. The stringent CAFE standards set forth by the Obama administration has pushed the automotive industry to radically revolutionize and design lightweight systems using advanced materials such as composites. Despite several outstanding benefits, advanced materials often come with additional costs. Minimizing physical infrastructure and improving efficiency will make the use of these materials affordable. This paper provides a thought provoking application of IIoT in automotive composites body shop.
2017-03-28
Technical Paper
2017-01-0289
Mojahed M. Alkhateeb, J Rickli, Ahmed al-mirza, Jovan Morgan
3D scanners digitally capture the shape of physical objects. 3D scanners have been mounted to a robot in an effort to automated the scanning and inspection process. Robots moves the 3D scanner over the surface of on object to collect the point cloud of the surface. Point clouds of the surface are collected and forms a digital representation of an object. The kinematic relationship between the component surface of the part being scanned, robot, and scanner were derived in the past. However, the location of the point on the physical surface and acquired point cloud collected by the 3D scanner cannot be compared because the relationship between the two workspaces were not found. In this work we derive the transformation for the robot workspace and the scanner workspace (C-track camera space) to be able to know the location of a point being collected on the robot workspace.
2017-03-28
Technical Paper
2017-01-1513
Young-Chang Cho, Chinwei Chang, Andrea Shestopalov, Edward Tate
The airflow into the engine bay of a passenger car is used for cooling down essential components of the vehicle, such as powertrain, air-conditioning compressor, intake charge air, batteries, and brake systems, before it returns back to the external flow. When the intake ram pressure becomes high enough to supply surplus cooling air flow, this flow can be actively regulated by using arrays of grille shutters, namely active grille shutters (AGS), in order to reduce the drag penalty due to excessive cooling. In this study, the operation of AGS for a generic SUV-type model vehicle is optimized for improved fuel economy on a highway drive cycle by using surrogate models. Both vehicle aerodynamic power consumption and under-hood cooling performance are assessed by using PowerFLOW, a high-fidelity flow solver that is fully coupled with powertrain heat exchanger models.
2017-03-28
Technical Paper
2017-01-1240
Koki Matsushita
Demands for improving fuel economy and reducing carbon dioxide emmision in automobiles have been increasing rapidly. Since the ratio of alternator loss to entire loss of automobile is high, reducing the alternator loss is effective for fuel economy improvement. The alternator loss consists of three main losses; copper loss, iron loss and rectification loss. Above all, the ratio of rectification loss to the alternator loss, which is approximately 30%, is relatively high. DENSO has developed “MOS rectifier” to reduce the rectification loss. The MOS rectifier is a commutating device which has MOSFETs as rectifying devices instead of diodes. The MOS rectifier contributes to fuel economy improvement of automobiles by reducing rectification loss with low On-Resistance(Ron) MOSFET. Since the MOS rectifier is exposed to severe temperature environment from -40 °C to 120 °C, temperature stress on solder and Aluminium wire is large.
2017-03-28
Technical Paper
2017-01-0315
Yueqian Jia, Yangyang Qiao, Hao Pan, Edmund Chu, Yuanli Bai
A comprehensive plasticity and fracture model was built for metal sheets with application to sheet forming and vehicle crash simulations. The Bai-Wierzbicki (BW) plasticity model was extended consider material anisotropy, strain rate and high 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-monotonic loading conditions. The modified Mohr-Coulomb (MMC) fracture model was extended to consider material anisotropy, high temperature effects 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
Technical Paper
2017-01-1239
Naoya Take, Takuya Kadoguchi, Masao Noguchi, Kimihiro Yamanaka
Power modules are used to operate three-phase alternative motors in hybrid vehicles and electric vehicles. The good fuel efficiency and high power density are requested in the field of hybrid vehicles. To achieve this goal, the miniaturization of power module will be necessary. This trend may make current density, which is operated by insulated gate bipolar transistors (IGBTs) and Free wheel diodes (FWDs), higher in power modules. Solder is often used as the joint material of power modules. It is known that a current density larger than 10 kA/cm2 causes solder electromigration which exchanges momentum from electrons to metallic atoms .This phenomenon may cause delamination of the joint area and void formation. In addition, the ambient temperature has an influence on electromigration. The temperature of an engine compartment is high, so it is likely to cause electromigration.
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