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A 3.4 kW, 42 V permanent magnet alternator based high power generation system was built and tested in the Delphi R&D laboratory. It is belt driven system with 3.37: 1 pulley ratio. The size of the alternator is slightly less than the production CS-144 Lundell machine with 1/3 less inertia. For cost reasons, the controller uses a single SCR bridge rectifier. The prototype, which is capable of producing 34A/80A at idle/cruising speed, has been tested in the laboratory yielding 84.5%/70.7% efficiencies. Up to cruising speed, the system shows an improvement in full load efficiencies of 5-6 percentile points over a similar 14 V permanent magnet machine with dual SCR bridge. This efficiency improvement is due to the reduction in the converter losses as the current is reduced to one third of its 14 V values even with the same copper losses in both machines.

Metal fiber DPF system is cheaper and more endurable than ceramic filter; however, the regeneration near the wall (outer layer) is difficult because of the heat loss and the less gas flow rate near the wall. In this study, a 3D CFD simulation is performed to find the flow control method for the more uniform mass flux for all filter layer. The major control factors are filter porosity, distribution plate and swirler. By placing the distribution plate in front of the filter the flow near the wall can be increased. The optimum place and size was chosen. The swirler can increase the flow more near the wall.

The focus of this paper is to develop an innovative vehicle layout and optimize vehicle body structure with the latest lightweight steel technologies, such as hydro-forming and hot stamping. Our BIW structure achieved a mass savings of 28 kg (−10%) compared to the mass of baseline BIW structure. (Base BIW : MD_Elantra)

Wear of brake disc is normally faced with sophisticated experimental methods, a basic overview on the phenomena related to disc wear is presented in this paper. DTV consists in a heterogeneous wear of the disc surface and it is caused by two factors: run-out and the mechanism of disc wear. The importance of DTV is due to the vehicle vibrations that high DTV values can cause during braking. A model, that considers iron oxide layer evolution on disc surface, can evidence some of the principal characteristics of disc wear. In this model the wear rates of disc gray cast iron and iron oxide layer are considered as some of the principal factors in DTV evolution, as well as the kinetics of the chemical reactions involved.

To date the market for P/M stainless steel has not developed appreciably, and has centered largely on the development of austenitic 300 series stainless steels. Although these stainless steels are noted for their resistance to corrosion in many media, it has been difficult for P/M parts fabricators to produce parts that will sustain 1,000 hours of protection in a 5% salt solution. The problem starts with the water atomized powders and continues with the sintering practice exercised to produce the parts. Reasons for lack of corrosion resistance, based upon these considerations, will be discussed. In addition, the ferritic stainless steels are being considered seriously for fuel injectors. These emerging applications derive from the corrosive environment that may become a problem if and when alternative fuels are introduced. P/M ferritic stainless steels may also assume a position as a corrosion resistant magnetic material required in ABS systems which are currently emerging.

A technique for determining induction system deposit (ISD) tendencies of a gasoline is described. The technique uses a bench apparatus, designed to simulate the valve and port area of an engine intake system, which provides deposit data correlative to real engines. The apparatus is compact, requires a minimal fuel sample, uses a retainable metal tube as the deposit collecting surface, and has good repeatability. Design of the equipment eliminates the possibility of deposit contamination by dirt, rust and lead precipitate, and both solvent-washed and unwashed data may be obtained. ASTM Gum, engine intake deposit weights, and ISD technique data are compared to illustrate the capabilities of this new technique.

A pin and disc machine has been modified for the evaluation of silver-steel lubrication characteristics of railroad diesel oils. Use of silver pins on polished steel discs at selected loads and rubbing speeds allows good correlation with known engine behavior. In comparison with wear and friction data obtained by the four ball method, this pin and disc test gives better correlation with engine tests than the Modified Four Ball Test.

Springback is a serious problem in sheet metal stamping. It measures the difference between the final shape of the part and the shape of the forming die. Sheet metal forming simulation has made significant progress in predicting springback and several computer simulation codes are commercially available to predict and compensate for it in tool design. The accurate prediction of springback is important and there is a need to validate and verify those predictions with experimental results. Current validation techniques lack standardized procedures, require measurement fixtures that may impose unrealistic restraint on the part, require profiling equipment such as CMM or laser scanning and for the most part produce small springback which reduces measurement accuracy and increases experimental error. A benchmark test has been developed which addresses all these concerns and compares springback predictions by various numerical simulation codes with each other and with experimental results.

Experimental procedures and results of a benchmark test for springback are reported and a complete suite of obtained data is provided for the validation of forming and springback simulation software. The test is usually referred as the Slit-Ring test where a cylindrical cup is first formed by deep drawing and then a ring is cut from the mid-section of the cup. The opening of the ring upon slitting releases the residual stresses in the formed cup and provides a valuable set of easy-to-measure, easy-to-characterize springback data. The test represents a realistic deep draw stamping operation with stretching and bending deformation, and is highly repeatable in a laboratory environment. In this study, six different automotive materials are evaluated.

The existing market conditions place heavy demands on the steel foundries to increase their capacity and output. Expansion hinges on the ability of the foundry to “earn the dollar” to permit the modernization of existing facilities and construction of new plants. It also requires that the foundry industry modernize its production methods and techniques; update its equipment; and that the consumer engineer assist in developing casting design features that will be more readily adaptable to the capabilities of the foundry operation. “A Bigger Payload from Steel Foundries” requires more than physical expansion-it demands cooperative and intelligent endeavor on the part of foundry management and consumer engineering.

HIGH load-carrying ability and fatigue strength, good embeddabiltty and conformability, and resistance to wear, seizure, and corrosion are factors that sold them on aluminum for bearings, the authors report. Bonded steel backing, they say, makes aluminum bearings even better. Retaining aluminum's good properties, it improves some of its bad points and gives such advantages as: Reduced bearing clearances, compared with those used with solid-aluminum bearings. No life limit in operation below 5000 psi fatigue stress value. Less sensitivity to high oil temperatures. Negligible wear (after 29,000 hr in one test). Simpler and less expensive bearing-locating designs. Special excellence for high-load, high-speed applications.

Fundamental differences exist between sheet metal forming and hydroforming processes. Sheet metal forming is basically a one step metal fabrication process. Almost all plastic deformation of an originally flat blank is introduced when the punch is moved normal to a clamped sheet metal. Hydroforming, however, consists of multiple steps of tube making, pre-bending, crushing, pressurization, etc. Each of the above mentioned steps can introduce permanent plastic deformations. The forming limit diagram obtained for sheet metal forming may or may not be used in hydroforming evaluations. A failure criterion is proposed for predicting bursting failures in tube hydroforming. The tube material's stress-strain curve, obtainable from uniaxial tensile test and subjected to some postulations under large stress/strain states, is used in judging the failure.

During the last several years the use of magnesium die-castings for automotive applications has been on the rise. Magnesium's use in die-cast form has been expanding at an average growth rate of more than 15% a year. Reasons for the increase are both practical and economic. Magnesium die-castings offer components having the lowest mass when compared to almost any other structural material. Magnesium die-alloys exhibit properties that bridge the gap between engineered plastics and metals. The mechanical performance ratios (strength-to-weight and stiffness-to-weight) of magnesium also compete favorably with metals and plastics. Economically, magnesium alloys prices have fallen during the last several years making them extremely competitive with other materials.

The prime function of crown wheel pinion is to receive the power from transmission & distribute to two-wheel ends. Doing so these members will experience the tremendous bending fatigue. Shot peen is the one of the latest technology used to improve the bending fatigue of the CWP [1]. In this particular case- six CWP are taken for the study to understand the effect of the operations after shot peen process. Three Samples are named as batch A, another 3 samples are named as batch B. Both the batch CWP are shot peened. Then as a regular production practice the batch A CWP are process through hard turning ➔ Abrasive lapping ➔ Hot lubriting (manganese phosphate) ➔ Fully finish ready for assembly. Then both the batch A & batch B samples are taken for residual stress analysis using X-Ray diffraction technique. The measurement location is 50 microns below the surface. The results tabulated, found that batch A samples shows decrease in Residual stress relatively to batch B.

In the late 1940’s Alcoa began marketing forged aluminum disc wheels for Class VII and VIII highway tractors, and in 1972 stylized passenger car wheels. This paper covers the evolution of some early pre-production designs to the present.

A unique heat exchanger has been developed with potential applications for cooling high power density electronics and perhaps high energy laser mirrors. The device was designed to absorb heat fluxes of approximately 50 w/cm2 (158,000 Btu/hr.ft2) with a low thermal resistance, a high surface temperature uniformity and very low hydraulic pumping power. A stack of thin copper orifice plates and spacers was bonded together and arranged to provide liquid jet impingement heat transfer on successive plates. This configuration resulted in effective heat transfer coefficients, based on the prime surface, of about 85,000 w/m2 °C (15,000 Btu/hr.ft2 °F) and 1.8 watts (.002 HP) hydraulic power with liquid Freon 11 as coolant.

Precipitation Hardened Stainless Steel (PHSS) is one of the martensitic steels that possess exceptional strength and corrosion resistance. Because of its characteristics, this PHSS is exclusively adopted in numerous engineering uses such as nuclear, chemical and marine industries. Welding is one of the important methods of joining that helps to make weldments with better performance characteristics. Corrosion behaviour is one of the important characteristics that contribute hugely to marine and other corrosion-related environments and also this is the most common problem for most of the manufacturing industries. The goal of this study was to analyze the PHSS weldments’ corrosive behavior and compare it with that of the two commonly used welding processes, namely MIG and TIG. The corrosive properties of the weldments were evaluated using various mediums, such as nitric acid, ferric chloride, and Oxalic acid.

The demand for vehicles with improved NVH characteristics, fuel economy and emissions control has increased dramatically in recent years. To meet these objectives stiffer and lighter housings are required so as to avoid troublesome driveline vibrations, while at the same time produce lighter structures to reduce the overall vehicle weight and improved fuel economy. A feasibility study was undertaken to examine the differences between the use of magnesium alloy and aluminium alloy for an automatic transmission converter housing. The design process, design constraints, design methodology, alloy selection and some unique magnesium design requirements are outlined. The differences between the two designs are investigated by simulating their static and dynamic performances using Finite Element Analysis (FEA). A sand cast prototype was produced for the first stage of the feasibility study, with the ultimate aim to produce die cast magnesium converter housings if feasible.