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Viewing 61 to 90 of 19997
2015-04-14
Journal Article
2015-01-0604
Jibrin Sule, Supriyo Ganguly
Abstract In a multi-pass weld, the development of residual stress to a large extent depends on the response of the weld metal, heat affected zone and parent material to complex thermo-mechanical cycles during welding. Previous investigations on this subject mostly focused on mechanical tensioning or heat treatment to modify the residual stress distribution in and around the weld. In this research, microstructural refinement with modification of residual stress state was attempted by applying post weld cold rolling followed by laser processing. The hardening of the weld metal was evaluated after welding, post weld cold rolling and post weld cold rolling followed by laser processing. The residual stress was determined non-destructively by using neutron diffraction. Hardness results showed evidence of plastic deformation up to 4 mm below the weld surface.
2015-04-14
Technical Paper
2015-01-0705
Koichi Taniguchi, Hiroshi Matsuda, Rinsei Ikeda, Kenji Oi
Abstract We have developed a new resistance spot welding process with “pulsed current pattern”, which consists of short-time high-current post-heating and short-time cooling to improve joint strength of ultra high strength steel (UHSS) sheets with a tensile strength over 980MPa. The high-current post-heating reheats the heat affected zone (HAZ) near the electrodes and that near the sheet-sheet interface rather than the center of the nugget, and this pulsed current pattern utilizes this procedure to improve the toughness of the nugget. In the case of 980MPa grade steel with a 1.6mm thickness, the pulsed current pattern improved cross tension strength (CTS) from 7.2kN to over 10kN and its failure mode from interface failure to plug failure.
2015-04-14
Journal Article
2015-01-0706
Zheng-Ming Su, Pai-Chen Lin, Wei-Jen Lai, Jwo Pan
Abstract In this paper, failure modes of dissimilar laser welds in lap-shear specimens of low carbon steel and high strength low alloy (HSLA) steel sheets are investigated based on experimental observations. Micro-hardness tests across the weld zones of dissimilar laser welds were conducted. The hardness values of the fusion zones and heat affected zones are significantly higher than those of the base metals. The fatigue lives and the corresponding failure modes of laser welds as functions of the load ranges are then examined. Optical micrographs of the laser welds before and after failure under quasi-static and cyclic loading conditions are then examined. The failure modes and fatigue behaviors of the laser welds under different loading conditions are different. Under quasi-static loading conditions, a necking failure occurred in the upper low carbon steel sheet far away from the laser weld.
2015-04-14
Journal Article
2015-01-0708
Catherine M. Amodeo, Jwo Pan
Abstract In this paper, mode I and mode II stress intensity factor solutions for gas metal arc welds in single lap-shear specimens are investigated by the analytical stress intensity factor solutions and by finite element analyses. Finite element analyses were carried out in order to obtain the computational stress intensity factor solutions for both realistic and idealized weld geometries. The computational results indicate that the stress intensity factor solutions for the realistic welds are lower than the analytical solutions for the idealized weld geometry. The computational results can be used for the estimation of fatigue lives in a fatigue crack growth model under mixed mode loading conditions for gas metal arc welds.
2015-04-14
Journal Article
2015-01-0744
Terrence Alger, Raphael Gukelberger, Jess Gingrich, Barrett Mangold
Abstract The use of cooled EGR as a knock suppression tool is gaining more acceptance worldwide. As cooled EGR become more prevalent, some challenges are presented for engine designers. In this study, the impact of cooled EGR on peak cylinder pressure was evaluated. A 1.6 L, 4-cylinder engine was operated with and without cooled EGR at several operating conditions. The impact of adding cooled EGR to the engine on peak cylinder pressure was then evaluated with an attempt to separate the effect due to advanced combustion phasing from the effect of increased manifold pressure. The results show that cooled EGR's impact on peak cylinder pressure is primarily due to the knock suppression effect, with the result that an EGR rate of 25% leads to an almost 50% increase in peak cylinder pressure at a mid-load condition if the combustion phasing is advanced to Knock Limited Spark Advance (KLSA). When combustion phasing was held constant, increasing the EGR rate had almost no effect on PCP.
2015-04-14
Technical Paper
2015-01-0733
Nichole Verwys, Jesse Fritcher, Thomas DeMass
Abstract Dark, high gloss decorative finishes (i.e. piano black) are gaining increased application and demand in vehicle interiors; due to interior stylists' desire for this look. One significant concern with this trend is that scratches, and other appearance related defects such as orange peel (waviness), are more apparent to the customer. To address this issue, a highly scratch-resistant 2K clearcoat formulation was developed to minimize visible surface scratches, while also yielding minimal orange peel and exceptional DOI (distinctness of image); all while being applied using typical application techniques in the part finishing market. This output was accomplished by first benchmarking the consumer electronics market for appearance and scratch resistance, and then setting targets through that research.
2015-04-14
Journal Article
2015-01-1754
Wei-Jen Lai, Jwo Pan
Abstract In this paper, the analytical stress intensity factor and J integral solutions for welds in lap-shear specimens of two dissimilar sheets based on the beam bending theory are first reviewed. The solutions are then presented in the normalized forms. Next, two-dimensional finite element analyses were selectively conducted to validate the analytical solutions based on the beam bending theory. The interface crack parameters, the stress intensity factor solutions, and the J integral solutions for welds in lap-shear specimens of different combinations of steel, aluminum, and magnesium, and the combination of aluminum and copper sheets of different thickness ratios are then presented for convenient fracture and fatigue analyses. The transition thickness ratios for critical crack locations for different combinations of dissimilar materials are then determined from the analytical solutions.
2015-04-14
Journal Article
2015-01-1319
Eitaro Koya, Yukihide Fukuda, Shinya Kitagawa, Mitsunori Murakami, Atsushi Kawauchi, Sadanori Furue
Abstract When using aluminum for vehicle body parts to reduce weight, the high pressure die casting (HPDC) is widely applied due to its adaptability to thin-wall products, near-net-shape castability, and short casting cycle time. Since a hollow construction is advantageous to increase stiffness of body parts, there has been a need of development of techniques for casting of hollow parts by HPDC. So far, hollow casting by HPDC has been realized for small parts using sand cores. When applying that method to large parts, however, it is necessary to increase filling speed. When the filling speed is increased, the core tends to break. In this project, we have developed a method to estimate changes of pressure distribution when filling molten metal by the casting simulation in order to analyze damages to the core. Through the analysis, we discovered occurrence of impulsive pressure waves.
2015-04-14
Journal Article
2015-01-0530
Mikko Joonas Kähkönen, Emmanuel De Moor, John Speer, Grant Thomas
Abstract Quenching and partitioning (Q&P) is a novel heat treatment to produce third generation advanced high-strength steels (AHSS). The influence of carbon on mechanical properties of Q&P treated CMnSi-steels was studied using 0.3C-1.5Mn-1.5Si and 0.4C-1.5Mn-1.5Si alloys. Full austenitization followed by two-step Q&P treatments were conducted using varying partitioning times and a fixed partitioning temperature of 400 °C. The results were compared to literature data for 0.2C-1.6Mn-1.6Si, 0.2-3Mn-1.6Si and 0.3-3Mn-1.6Si Q&P treated steels. The comparison showed that increasing the carbon content from 0.2 to 0.4 wt pct increased the ultimate tensile strength by 140 MPa per 0.1 wt pct C up to 1611 MPa without significantly decreasing ductility for the partitioning conditions used. Increased alloy carbon content did not substantially increase the retained austenite fractions.
2015-04-14
Journal Article
2015-01-0512
Anthony D. Prescenzi
Abstract Ablation casting is an emerging technology which combines traditional sand molding techniques with rapid cooling due to the use of a water soluble binder. High cooling rates and control of solidification direction allows for exceptional mechanical properties and complex shapes. Through the use of ablation, six different body node castings have been manufactured for the 2016 NSX aluminum space frame. The high mechanical properties allowed these castings to be integrated into the crash structure for energy absorption. Using the traditional casting alloy A356, target mechanical properties were 190 Mpa Yield Strength, 280 Mpa Tensile Strength and 12% min elongation. The high elongation was achieved due to the refined eutectic microstructure produced by high cooling rates. The eutectic microstructure produced by ablation was found to be Level 5 or 6 on the AFS scale. Light weighting could also be achieved when compared to traditional GDC castings.
2015-04-14
Journal Article
2015-01-0519
Susumu Maeda, Atsushi Kobayashi, Yuichiro Shimizu, Masao Kanayama, Masato Yuya, Hideki Imataka
Abstract A new nitriding technology and material technology have been developed to increase the strength of microalloyed gears. The developed nitriding technology makes it possible to freely select the phase composition of the nitride compound layer by controlling the treatment atmosphere. The treatment environment is controlled to exclude sources of supply of [C], and H2 is applied as the carrier gas. This has made it possible to control the forward reaction that decomposes NH3, helping to enable the stable precipitation of γ′-phase, which offers excellent peeling resistance. A material optimized for the new nitriding technology was also developed. The new material is a low-carbon alloy steel that makes it possible to minimize the difference in hardness between the compound layer and the substrate directly below it, and is resistant to decline in internal hardness due to aging precipitation in the temperature range used in the nitriding treatment.
2015-04-14
Journal Article
2015-01-0525
Constantin Chiriac, Ming F. Shi
Abstract Automotive structural parts made out of Advanced High Strength Steel (AHSS) are often produced in a multistage forming process using progressive dies or transfer dies. During each forming stage the steel is subjected to work hardening, which affects the formability of the steel in the subsequent forming operation. Edge flanging and in-plane edge stretching operations are forming modes that are typically employed in the last stage of the multistage forming processes. In this study, the multistage forming process was simulated by pre-straining a DP980 steel in a biaxial strain path with various strain levels followed by edge flanging and in-plane edge stretching. The biaxial prestrains were obtained using the Marciniak stretch test and edge flanging and in-plane edge stretching were accomplished by the hole expansion test using a flat punch and a conical punch, respectively.
2015-04-14
Technical Paper
2015-01-0531
Hiroyuki Yamashita, Hiroaki Ueno, Hiroyuki Nakai, Takahiro Higaki
Abstract When the strain is temporarily stopped during tensile testing of a metal, a stress relaxation phenomenon is known to occur whereby the stress diminishes with the passage of time. This phenomenon has been explained as the change of elastic strain into plastic strain. A technique was devised for deliberately causing strain dispersion to occur by applying the stress relaxation phenomenon during stamping. A new step motion that pause the die during forming was devised; it succeeded in modifying the deep-draw forming limit by a maximum of 40%. This new technique was verified through tensile and actual stamping tests. It was confirmed that the use of step motion causes the strain to disperse, thereby modifying the deep draw forming limit. The degree to which the forming limit is modified is dependent on the stop time and the temperature.
2015-04-14
Technical Paper
2015-01-1736
Justin Cartwright, Ahmet Selamet, Robert Wade, Keith Miazgowicz, Clayton Sloss
Abstract The heat rejection rates and skin temperatures of a liquid cooled exhaust manifold on a 3.5 L Gasoline Turbocharged Direct Injection (GTDI) engine are determined experimentally using an external cooling circuit, which is capable of controlling the manifold coolant inlet temperature, outlet pressure, and flow rate. The manifold is equipped with a jacket that surrounds the collector region and is cooled with an aqueous solution of ethylene-glycol-based antifreeze to reduce skin temperatures. Results were obtained by sweeping the manifold coolant flow rate from 2.0 to 0.2 gpm at 12 different engine operating points of increasing brake power up to 220 hp. The nominal coolant inlet temperature and outlet pressure were 85 °C and 13 psig, respectively. Data were collected under steady conditions and time averaged. For the majority of operating conditions, the manifold heat rejection rate is shown to be relatively insensitive to changes in manifold coolant flow rate.
2015-04-14
Technical Paper
2015-01-0238
Nick Smith
Abstract Manufacturing companies are benefiting from technology in most key areas of the flow from design through manufacture. This applies to the wire harness industry which is a key element of the modern automotive industry. Wire harness manufacturing engineering, however, is a critical path function that is under severe pressure and yet has been under-served by technology. In some respects it has become the weak link in the chain. Recent innovations in commercial off-the-shelf (COTS) technology are set to change this situation. Software applications are now available to deliver transformational manufacturing engineering automation as well as being able to integrate with technology in other areas of the process. This will enable a digitally continuous data flow that can remove excessive cost, time, and pressure - while helping manufacturers meet the increasing demands of the industry.
2015-04-14
Journal Article
2015-01-1311
Leland Decker, James Truskin
Abstract As CAFE requirements increase, automotive OEMs are pursuing innovative methods to lightweight their Body In Whites (BIWs). Within FCA US, this lightweighting research and development activity often occurs through Decoupled Innovation projects. A Decoupled Innovation team comprised of engineers from the BIW Structures Group, in collaboration with Tier 1 supplier Magna Exteriors, sought to re-design a loadbearing component on the BIW that would offer significant weight savings when the current steel component was replaced with a carbon fiber composite. This paper describes the design, development, physical validation and partnership that resulted in a composite Rear Package Shelf Assembly solution for a high-volume production vehicle. As the CAFE requirements loom closer and closer, these innovation-driven engineering activities are imperative to the successful lightweighting of FCA US vehicles.
2015-04-13
Article
Halla Visteon Climate Control Corp. (HVCC) recently began production at its new facility in Sanand, in the state of Gujarat, India. The full-line supplier of automotive thermal management solutions is using the Gujarat facility to support its growing business with global vehicle manufacturers and to cater to the requirements of OEMs in the state of Gujarat and western India.
2015-04-10
WIP Standard
AMS2477B
This specification covers the requirements for a low-electrical-resistance chemical conversion coating on aluminum and aluminum alloy parts.
2015-04-10
WIP Standard
AMS2546A
This specification covers the requirements for computer controlled laser peening of metal part surfaces to induce residual compressive stresses at and beneath the surface.
2015-04-10
WIP Standard
AMS2755G
This specification has been declared “CANCELLED” by the Aerospace Materials Division, SAE, as of July 2009. By this action, this document will remain listed in the Numerical Section of the Index of Aerospace Material Specifications indicating that it has been “CANCELLED”. Cancelled specifications are available from SAE.
2015-04-10
WIP Standard
AMS3084C
This specification covers a solid film lubricant in the form of a ready-to-use, sprayable suspension.
2015-04-10
WIP Standard
AMS2680D
This specification defines the procedures and requirements for joining metals and alloys using the electron-beam welding process.
2015-04-10
Standard
AMS5045J
This specification covers a carbon steel in the form of sheet and strip.
2015-04-10
WIP Standard
AMS2410L
This specification covers the engineering requirements for electrodeposition of silver on other metals, usually with a nickel strike between the basis metal and the silver.
2015-04-10
WIP Standard
AMS2449A
This specification covers engineering requirements for the grinding of tungsten carbide High Velocity Oxygen/Fuel (HVOF) thermal spray coatings applied to high strength steels (220 ksi and above). This process has been used typically to grind tungsten carbide HVOF coatings applied in accordance with AMS 2447 or AMS 2448 to high strength steels for applications requiring wear, heat, and corrosion resistance or dimensional restoration, such as aircraft landing gear components, However, usage is not limited to such applications. This process specification does not cover superfinishing of HVOF applied coatings.
2015-04-10
Standard
AMS5629/H1000A
This specification covers a corrosion-resistant steel product in the solution and precipitation heat treated (H1000) condition.
2015-04-10
WIP Standard
AMS2424G
This specification covers the engineering requirements for electrodeposition of a low-stressed nickel and the properties of the deposit.
2015-04-10
Standard
AMS5659R
This specification covers a corrosion-resistant steel in the form of bars, wire, forgings, flash welded rings, and extrusions in the solution heat treated condition (See 8.3), and stock for forging, flash welded rings, or extruding.
2015-04-10
WIP Standard
AMSP81728B
This specification covers the requirements for electrodeposited tin-lead plating intended for use as a coating for corrosion protection and as a base for soldering.
2015-04-09
Standard
J1339_201504
This SAE Recommended Practice is intended for use in testing and evaluating the approximate performance of engine-driven cooling fans. This performance would include flow, pressure, and power. This flow and pressure information is used to estimate the engine cooling performance. This power consumption is used to estimate net engine power per SAE J1349. The procedure also provides a general description of equipment necessary to measure the approximate fan performance. The test conditions in the procedure generally will not match those of the installation for which cooling and fuel consumption information is desired. The performance of a given fan depends on the geometric details of the installation, including the shroud and its clearance. These details should be duplicated in the test setup if accurate performance measurement is expected.
Viewing 61 to 90 of 19997

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