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Design specifications for suspensions of passenger cars for ride and handling in the past half century were amazingly associated with some “Magic Numbers.” These parameter values are needed for mathematical models which describe the dynamic motions of a vehicle on the road, help researchers to validate the overall performance of their simulations. Moreover, these numbers should be viewed as a guide for evaluation of vehicle design practice for moderate payload and driving conditions. Number 1, for instance, is the magic number associated with bounce resonant frequency of the sprung mass, but also related to the desired value for the dynamic index for ride quality and directional control. Number 10, on the other hand, is the magic number associated with wheel hop resonant frequency and the desired total mass/-unsprung masses ratio.

The characteristics of maglev systems being considered for implementation in the United States are speculative. A conference was held at Argonne National Laboratory on November 28-29, 1990, to discuss these characteristics and their implications for the design requirements of operational systems. This paper reviews some of the factors considered during that conference.

This is an assessment of United States High Speed Guided Transit (HSGT) systems policy, vision, goals, and magnetic levitation development and commercialization technology; as affected by the new United States National Energy Strategy. It includes a brief review of the key aspects and assumptions which formed the basis for the US National Energy Strategy scenario, and the tactics proposed to implement a National Maglev transit network by the target year 2015 (1)1. It is followed by a historical review of past magnetic levitation vehicle developments, a review of the present status of Maglev trains, and an outline of future (EMA) Electro Magnetic Attraction levitation for speeds under 400 km/h; (SC) Super Conductive (EDR) Electro Dynamic Repulsion levitation for subsonic speeds approaching 900 km/h; and, an introduction to the (MPW) Magnetic Potential Well levitation effect as developed by Kozoriz (2) in 1976, also see (39).

Maglev is the generic label for a family of technologies, including two modes of magnetic suspension (attraction and repulsion), magnetic guidance and linear electric drives for applications from shuttle service to intercity transportation. Low-speed systems are in service. Intermediate- and high-speed systems are at an advanced prototype development, testing and demonstration phase. This paper reviews the modes of Maglev, the status of system development, and the prospects for implementation. The evolution towards technological maturity is such that Maglev is a realistic transportation option for the nineties.

In response to ever more challenging global fuel economy and environmental regulations, automakers will rely on lightweighting to continue to meet the established goals. As “bolt-on” subassemblies, closure panels provide a unique opportunity to tailor the vehicle mass to achieve local environmental compliance relative to a global vehicle platform while maintaining equivalent functionality and safety performance. This paper is aimed at communicating the results of a life cycle assessment (LCA) study which compares the lightweight auto parts of the new Magna’s Ultralight Door design to the conventional auto parts of the baseline 2016 MY Chrysler 200C 6 cyl, 3.6 L, automatic 9-spd, an ICE vehicle (gasoline fueled) built and driven for 250,000 km in North America (NA) [1]. Magna International Inc. (Magna), in cooperation with the United States Department of Energy (U.S.

This paper outlines the use of Magnesium AM60B to provide the structural material for a one piece Die Cast Instrument Panel cross vehicle beam, to aid packaging, DFM/DFA, steering column modal, mass goals and Crashworthiness

A series of die cast AM50 magnesium test bars were made utilizing several design of experiment techniques in an attempt to determine if improved mechanical properties could be obtained. Process variables were selected and adjusted using a variables search technique during the sampling trails. Bars were tested for elongation, yield and tensile strength. Results show improved mechanical characteristics over those currently published. Findings show that temperature, pressure and gate velocity have the greatest influence on the ability of the AM50 alloy to reach the desired elongation percentages. In addition, the consistency of the high pressure die casing machine and accessory equipment had a direct effect on the success of the experiments.

At the Institute of Materials Science, University of Hanover in Germany, current research work is dealing with magnesium alloy development and modification for Space-Frame-Concepts in the automobile industry. At the moment several problems impede such a realization with magnesium similar to the Aluminum-Space-Frame Concept of Audi. Extruded magnesium alloys have a marked anisotropy concerning the position of the load to the extrusion direction as well as a concise tensile-compressive anisotropy. This article will give a small insight about the level of this research work and its development. Here possible solution attempts on the basis of commercial standard alloys are shown which do not only take into account the alloy modification but particularly also includes the materials processing for the production of extruded components.

The magnesium industry is in a growth trend thru the 1980s. The most accelerated growth will come from magnesium’s use in steel desulfurization and in die casting. It is expected that the automotive industry will be a significant part of this growth. Production capabilities will rise to meet the increase in demand through productivity improvements and expansion of existing facilities.

The last ten years has seen the North American automotive industry increasing its use of magnesium castings at an annual rate of around 15% and this rate of growth is expected to continue for at least the next ten years. The main driving force for this increasing use of magnesium is the need to reduce vehicle weight and improve fuel economy. Magnesium alloys are amongst the lightest structural materials available, however, they do cost more per unit mass than competing materials such as steel and aluminum and the automotive industry is reluctant to pay a premium for weight saving. However, in spite of an apparent cost penalty, magnesium castings are currently used in a number of automotive body, chassis and powertrain applications and this paper will review these applications. There is also a significant potential for future growth in the use of magnesium casting by the automotive industry where there may be little or no cost penalty.

The effective management of magnesium casting scrap involves a choice among several viable alternatives and techniques. Today's climate of diverse economic and environmental concerns preclude just a single “best approach” for all applications and locations. The various alternatives and options will be detailed along with their advantages and disadvantages. The best choice will depend on a caster's overall volume (or throughput), geographic location, existing facilities available, magnesium experience level, and several significant criteria.

Mechanical testing and prototyping of several developmental magnesium die cast alloys have shown that certain magnesium alloys can be exposed to temperatures in excess of 232°C (450°F) and still have adequate strength. For example, one of the alloys tested at 260°C (500°F) had a tensile yield strength greater than 87 HPa (12.7 ksi). Further testing also revealed that some of these alloys possess better creep strength at 316°C (600°F) than AZ91D has at 177°C (350°F) with at least as good castability as AS41A.

Magnesium die casting alloys for elevated temperature applications are coming of age. Several research centers and companies have been working on alloy systems based on alkaline earth and rare earth alloying additions to push the limits for the creep performance of Mg-based die casting alloys. Noranda's Mg-Al-Sr based alloys have shown superior creep performance and high-temperature performance at temperatures as high as 150-175C and stress levels of 50MPa - 70MPa. The most recent alloy formulation AJ62x (Mg-6Al-2Sr) has in addition shown excellent castability, and superior hot-tear resistance. Based on these attributes AJ62x is positioned well for applications such as transmission cases and oil pans. In this paper, the mechanical properties (creep and tensile) of AJ62x are presented. The high ductility of the AJ62Lx version is an added advantage for this alloy.

The integrated three-point safety belt for the driver and co-driver seat of the new Mercedes-Benz Roadster is the first of its kind to be utilized in a production car. The shoulder belt, including the automatic spool and belt preloading device, is incorporated in the seat back rest. This concept allows an adjustment of the belt geometry to nearly any passenger size, particularly in sports cars, which have no full-size middle post, and thus makes a major contribution to passive safety. Because of new magnesium alloys and improved casting techniques, it is now possible to produce the frame elements of the seat of high ductility magnesium pressure-die-casting, and thus ideally combine the requirements for mechanical strength, economy and production techniques.

The Structural Cast Magnesium Development Project is a jointly sponsored effort by the US Department of Energy (DOE) and the US Council for Automotive Research (USCAR) Automotive Metals Division (AMD) to identify and resolve technical and manufacturing issues that limit the light weighting opportunities of applying large-scale structural cast magnesium automotive components. This project, which began in the end of year 2001, comprises General Motors, Ford, DaimlerChrysler and thirty-four other North America companies and organizations. The project has its overall objective set to determine the technical feasibility and practicality of producing and implementing a one-piece front engine cradle casting. This paper provides an overview of the project scopes and up-to-date accomplishments.

Since the introduction of high purity magnesium die cast alloys, AZ91D and AM60B, many examples can be given of their ability to resist corrosion and accept a variety of decorative finishes. This paper will review the common finishing options available and the requirements for their proper application to die cast parts. The finishing systems employed in a number of commercial applications, past and present, using magnesium will be described.

A system has been constructed to estimate heat dissipated from geometrically identical heat sinks and pinfins extruded from magnesium (M1A) and aluminum (6063-T5)alloys. Two longitudinal fins of circular cross sectional area, machined from aluminum and magnesium, are used to calibrate the equipment. Thermocouples were mounted on an aluminum connecting cylinder between a heater and the pin fins or heat sinks. Insulation around this same cylinder and the heater keeps most of the heat flowing axially to be dissipated by the pin fins and heat sinks. Thermocouples were also mounted on the longitudinal fins to measure temperature distribution. Measured temperature distributions on the aluminum and magnesium pin fins were in good agreement with theoretical models. After calibration of the measuring equipment, the heat dissipated through actual aluminum and magnesium heat sinks was measured as a function of air velocity over the heat sinks.

AFTER reviewing briefly the history of the aluminum and magnesium industries, the author describes foundry practice in the production of magnesium and magnesium-alloy castings, their heat-treatment and the effect of various fabrication processes on the microstructure and physical properties. The general classes of commercial magnesium-base alloys now in use in this Country are discussed at some length with particular reference to the combination of extreme lightness with good physical and mechanical properties that is obtained. Applications of magnesium alloys in the aircraft and automobile industries are outlined in a section of the paper. Many of these are illustrated. In conclusion the author states that the importance of magnesium as a structural metal is now being recognized, especially as the factors that have retarded its development and restricted its use are overcome.

Recently, there have been substantial activities focusing on the development of magnesium alloys for high temperature applications (>150°C) through alloying additions, in order to expand its use. However, a simple route of improving the elevated temperature property of a magnesium alloy through the composite route has been overlooked. In particularly, the possibility of reinforcing a magnesium component through selective reinforcement has not been widely explored. In this paper, a viable technique of fabricating magnesium matrix composites through squeeze casting is provided. In addition, the novel approach of making preforms and the manner which they can be selectively reinforced into magnesium components is introduced. Finally, results on some of the key properties of magnesium composites developed by this technique along with the characterization results are presented.