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For years powder metal (P/M) nickel steel sprockets have been in use in the SUV Transfer Case market. The heat-treated, nickel steel powder metal provides a high strength and high wear resistant material for this very demanding application. Recently the cost of nickel has increased from $5 / lb Oct'05 to $24 / lb May'07. Because of this almost 5 fold increase in the commodity price a replacement material for the powder metal nickel steel was sought that would have comparable properties, comparable processing steps at a raw material cost that would be equal to the nickel steel powder metal prices of 2005. A replacement material was found that has comparable properties at a competitive price. Material composition, testing data and microscopic analysis will be presented.

An alternative to the current drum brakes, with the increased requirements of todays daily service are disc brakes, in that they offer, in contrast to the drum brakes, the following technical advantages and in turn enhance the active safety of modern commercial vehicles when braking: Enhanced brake pedal-feedback and actuation Improved efficiency Little performance losses when high thermal loads occur (fading). In order to be able to determine the improvement potential of disc brakes they will be compared to the commonly employed Simplex drum brakes. Both wheel brake systems (disc-/drum brakes and all variations) were tested on a computer controlled brake dynamometer and in field tests using a heavy duty commercial vehicle (class 8). The results are compared and conclusions drawn regarding “advantages/disadvantages”.

The double linear damage model developed by Manson and Halford helps to determine the knee point, which is the intersection between the two straight lines. The damage to the component is then calculated based on this knee point. The new approach mentioned in this paper helps to evaluate the damage on the component in a slightly different way. It uses the knee points as mentioned by Manson and Halford and decomposes the damage to the component for Phase I & Phase II. It then uses the equivalent damage approach and establishes the damage to the component. This will be explained with an example.

High frequency ignition (HFI) and conventional transistor coil ignition (TCI) were investigated with an optically accessible single-cylinder research engine to gain fundamental understanding of the chemical reactions taking place prior to the onset of combustion. Instead of generating heat in the gap of a conventional spark plug, a high frequency / high voltage electric field is employed in HFI to form chemical radicals. It is generated using a resonant circuit and sharp metallic tips placed in the combustion chamber. The setup is optimized to cause a so-called corona discharge in which highly energized channels (streamers) are created while avoiding a spark discharge. At a certain energy the number of ionized hydrocarbon molecules becomes sufficient to initiate self-sustained combustion. HFI enables engine operation with highly diluted (by air or EGR) gasoline-air mixtures or at high boost levels due to the lower voltage required.

Hydraulic, mechanical, and electro-magnetic technologies have been the primary means for torque management in today's drivetrains. Recent advances in electronic controls have provided even greater performance benefits for these base technologies. These facts coupled with an extended period of design and development for these drivetrain systems make the introduction of a new technology very challenging. However, recent developments at Borg Warner's Powertrain Technical Center have shown that a new technology, hydro-mechanical technology, may hold great promise in solving some of the fundamental problems and limitations of today's torque management technologies. This paper illustrates drivetrain applications where hydro-mechanical technology offers new and improved performance benefits for some of drivetrain's oldest problems. The opportunity to bring a new technology to the market in drivetrains also provides a new opportunity for powdered metallurgy (P/M) content in same.

Given the legal requirements for quality assurance of passenger car exhaust emissions worldwide we define our quality assurance system and present the emission laboratories of the Mercedes-Benz assembly plants Sindelfingen and Bremen. We developed a hierarchically structured, multi-level computer system, which enables us to automize emission test procedures, calibration, maintenance of measurement systems and documentation of exhaust data. Test cell computers coordinate the different components of the test cells and perform maintenance and calibration of measurement devices, thus guaranteeing a high measurement quality with reasonable economy. The coordinating level computer, the emission host system (EHS), processes test parameters, controls and supervises the test sequences and evaluates the test results on a statistical basis.

The purpose of this research was to present and analyze a previously unreported mechanism of injury within the automotive crash environment - spinal burst or compression fractures due to a vertical force component. Spinal burst fractures are comminuted fractures of the vertebral body which are often associated with retropulsed bone fragments into the spinal. Compression fractures are less traumatic fractures of the vertebral body with minimal comminution. Both fracture types can have varying degrees of neurologic deficit. The mechanism of injury is hypothesized to be a high energy compressive load along the axis of the spine initiated through the buttocks and pelvis or through torso augmentation (inertial loading of the lumbar spine by the torso). Four crashes are presented as evidence of this injury mechanism within the automotive crash environment: two in the United States and two in Germany.

With fuel costs continuing to rise, and with regulations seeking to lower overall fuel emissions, improved fuel economy has become indispensible for today's gasoline engine designer. Reducing engine friction is an effective means of improving fuel economy and specific engine components have been developed towards this objective. Chain drive system components are no exception to this trend. In an attempt to decrease friction loss in the timing chain system and thereby improving fuel economy, the following three topics were studied: 1) defining sources of friction loss; 2) investigating the effect(s) of each loss factor using friction simulation; and, 3) evaluating methods to minimize friction losses. Chain system friction loss can occur when the chain slides on the Arm & Guide face. Friction loss can also occur between the chain link and pin joint, and during chain engagement with the sprocket.