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Viewing 211 to 240 of 20088
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
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
2015-01-0706
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
2015-01-1316
Hwawon Lee, Parvath Police, Lisa Koch, Rajmouli Komarivelli, Brice Willis
Abstract Spot weld separation in vehicle development stage is one of the critical phenomena in structural analyses regarding quasi-static test condition, like roof strength or seat/belt pull. It directly reduces structural performance by losing connected load path and occasionally introduces tearing on surrounding sheet metals. Traditionally many efforts have been attempted to capture parent metal ductile fracture, but not applied to spot weld separations in automotive FEA simulations. [1,2,3] This paper introduces how to develop FFLD failure criteria from a series of parametric study on ultra high strength sheet steel and deals with failure criteria around spot weld and parent metal. Once the fracture strains for sheet steels are determined, those developed values were applied to traditional spot weld coupon FEA simulations and tests. Full vehicle level roof strength FEA simulations on a typical automotive body structure were performed and verified to the physical tests.
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
2015-01-1311
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.
2015-04-14
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
2015-01-1611
Wei Liu, Gangfeng Tan, Xuexun Guo, Jiafan Li, Yuanqi Gao, Wei Li
Abstract The hydraulic retarder is the most stabilized auxiliary braking system [1-2] of heavy-duty vehicles. When the hydraulic retarder is working during auxiliary braking, all of the braking energy is transferred into the thermal energy of the transmission medium of the working wheel. Theoretically, the residual heat-sinking capability of the engine could be used to cool down the transmission medium of the hydraulic retarder, in order to ensure the proper functioning of the hydraulic retarder. Never the less, the hydraulic retarder is always placed at the tailing head of the gearbox, far from the engine, long cooling circuits, which increases the risky leakage risk of the transmission medium. What's more, the development trend of heavy load and high speed vehicle directs the significant increase in the thermal load of the hydraulic retarder, which even higher than the engine power.
2015-04-14
Journal Article
2015-01-1722
Edmond Ilia, Giorgio Lanni, Kevin Tutton, Doug Sinclair
The advent of more efficient direct injection turbocharged engines has increased the need for higher performance connecting rods, able to withstand in particular higher compressive loads in operation. In this respect, new high strength materials for powder forged connecting rods were developed and introduced in production with excellent results. Among them, HS170M is currently used to manufacture connecting rods for several high performance engines, which not only have higher strength, but have less variation in their mechanical properties. The results of numerous benchmark studies have shown that powder forged connecting rods manufactured with HS170M are stronger than their steel forged counterparts manufactured with microalloyed steels, are easier to machine and fracture split, and represent a cost effective way to manufacture this important high reliability automotive component.
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
Standard
AMS5045J
This specification covers a carbon steel in the form of sheet and strip.
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
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
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
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
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
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
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.
2015-04-10
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
AMS2424G
This specification covers the engineering requirements for electrodeposition of a low-stressed nickel and the properties of the deposit.
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.
2015-04-07
Standard
AMS4824E
Form: This specification covers bearings of a leaded bronze cast on one or both faces of a steel backing with a layer of babbitt metal cast on the leaded bronze.
2015-04-06
Article
Turbine blades in TiAl are about half the weight of comparable nickel-alloy components but boast the same reliability and durability. The high aluminum content also makes the material resistant to oxidation and corrosion.
2015-04-05
WIP Standard
AMS4544H
This specification covers a corrosion-resistant nickel-copper alloy in the form of sheet, strip, and plate. These products have been used typically for formed or moderately-drawn parts requiring corrosion resistance, but usage is not limited to such applications.
2015-04-05
WIP Standard
AMS5356D
This specification covers a corrosion resistant steel in the form of investment castings.
2015-04-05
WIP Standard
AMS5716K
This specification covers a heat-resistant iron-nickel alloy in the form of bars, wire, forgings, flash welded rings, and stock for forging or flash welded rings.
2015-04-05
WIP Standard
AMS5803G
This specification covers a corrosion and heat-resistant steel in the form of welding wire.
2015-04-05
WIP Standard
AMS5762G
This specification covers a free-machining, corrosion-resistant steel in the form of bars, wire, forgings, and forging stock.

This product has been used typically for parts on which the amount of machining warrants use of a free-machining grade of steel, requiring corrosion resistance similar to the 18-8 type of steels but not subjected to temperatures exceeding 700 °F (371 °C) during fabrication or in service, but usage is not limited to such applications.

2015-04-05
WIP Standard
AMS5585H
This specification covers a corrosion and heat resistant alloy in the form of welded and drawn tubing.
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