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This paper demonstrates the possibilities of using Automotive waste plastic material from “end of life” vehicles (ELVs), in the Footwear Industry to manufacture shoe components. The study establishes the sustainability of the flow of ELVs, from the European Car Parc and identifies and estimates the quantity of plastic materials potentially available for recycling from ELVs. Four potential materials, Acrylonitrile/butadiene/styrene (ABS), Polypropylene (PP), Polypropylene/ethylene/propylene/diene (PP/EPDM) and Polyamide (PA), were identified and three materials (PP, PP/EPDM and ABS) were reprocessed from ELV components and evaluated by the Footwear Industry. As a result, ABS was recommended as an economically, suitable replacement for HIPS, the current material used for manufacturing shoe heel components.

An unique bonding mechanism was studied after several instances, where the linings stuck to the brake drums on transit buses, were reported. Evidences suggested that the linings were “glued” to the brake drums surface after wear debris (dust) was turned into “adhesive paste” through complicated thermal and chemical changes. Factors such as the friction materials, environment and service conditions, which could activate and deactivate the lining bonding, were observed and discussed. The prevention measures are proposed.

Proper lubrication of moving parts is a critical factor in internal combustion engine performance and longevity. Determination of ideal lubricant change intervals is a prerequisite to ensuring maximum engine efficiency and useful life. When oil change intervals are pushed too far, increased engine wear and even engine damage can result. On the other hand, premature oil changes are inconvenient, add to vehicle maintenance cost, and result in wasted natural resources. In order to determine the appropriate oil change interval, we have developed an oil condition sensor that measures the electrical properties of engine oil, and correlates these electrical properties to the physical and chemical properties of oil. This paper provides a brief background discussion of the oil degradation process, followed by a description of the sensor operational principles and the correlation of the sensor output with physical and chemical engine oil properties.

This paper presents, chemistry, test data and processing procedures on a non toxic and environmentally friendly chrome-free conversion coating alternative with the same level of adhesion and secondary corrosion resistance as that found in chrome containing conversion coating systems. Test data from military and independent sources will be presented on secondary coating adhesion, electrical conductivity, filiform and neutral salt-spray corrosion resistance as compared to chromate based systems .on magnesium, aluminum and zinc and their respective alloys. The European “RoSH” initiative will not allow for the presence of any hexavalent chromium on imported electrical components as of July first of 2006. Trivalent chromium based systems generate hexavalent chromium due to the oxidation of the trivalent chromium and as such will not be allowed.

This paper presents a fatigue criterion based on stress invariants for the frequency-based analysis of multiaxial random stresses. The criterion, named “Projection-by-Projection” (PbP) spectral method, is a frequency-based reformulation of its time-domain definition. In the time domain PbP method, a random stress path is first projected along the axes of a principal reference frame in the deviatoric space, thus defining a set of uniaxial random stress projections. In the frequency-domain approach, the damage of stress projections is estimated from the stress PSD matrix. Fatigue damage of the multiaxial stress is next calculated by summing up the fatigue damage of every stress projection. The criterion is calibrated on fatigue strength properties for axial and torsion loading. The calculated damage is shown to also depend on the relative ratio of hydrostatic to deviatoric stress components.

Research information on solid lubricants has been compiled for consideration in the possible use of such materials in aircraft electrical equipment. Solid lubricants are capable of lubricating at the maximum temperatures (600° F) for aircraft electrical equipment. Many solids that adhere well to metals may be useful lubricants; those with layer-lattice structure usually give low friction. Solid lubricants are most commonly used as bonded films but the use of fluid carriers and surface reaction products have considerable merit.

Nisshin Steel Co., Ltd. has developed a new process for the production of a “one-side aluminized steel sheet”. The process utilizes a double layer one-side “stop-off” coating to prevent the molten Al from adhering to the steel surface. The “Stop-off” coating is removed by simple mechanical brushing after hot dipping. The characteristics of this product by above mentioned process are: 1) The steel side was as clean as a conventional cold rolled surface and showed no trace of the “stop-off” layer. Thereby, phosphating and ED painting were performed. 2) In the salt spray test data was obtained from zinc and Al coated steel surfaces; the coatings on both surfaces being of equal thickness.

Engineers doing squeak and rattle testing of instrument panels (IP's) have successfully used large electrodynamic vibration systems to identify sources of squeaks and rattles (S&R's). Their successes led to demands to test more IP's, i.e., to increase throughput of IP's to reflect the many design, material, and/or manufacturing process changes that occur, and to do so at any stage of the development, production, or QA process. What is needed is a radically different and portable way to find S&R's in a fraction of the time and at lower capital cost without compromising S&R detection results.

Engineers have long been restricted in designing and manufacturing one piece, hollow composite components with complex internal geometry. Complex core pulls in the plastic tool, major concessions made in the actual component design or components joined from several pieces were the early means of producing such components. Progressive thinking led to the use of matrix materials such as sand, salt and wax, which provided a measure of flexibility in allowing designed-in undercut areas. These materials, however, lacked the capability to meet the required demands of dimensional accuracy and internal surface, as well as proving themselves unsuitable for high volume production. The concerns for repetitive dimensional accuracy, quality internal surface and high volume production capability has now been satisfied with the use of low melting temperature metal alloys.

“In-car” measurement of vehicle loads and stresses is a basic step in solving fatigue design problems associated with passenger cars. The application includes measuring systems and techniques for evaluating fatigue design problems related to energy-absorbing steering columns and automotive gas turbines.

Automotive industry is a major contributor to global carbon dioxide (CO2) emissions and waste generation. Not only do vehicles produce emissions during usage, but they also generate emissions during production phase and end of life disposal. There is an urgent need to address sustainability and circularity issues in this sector. This paper explores how circularity and CO2 reduction principles can be applied to design and production of automotive parts, with the aim of reducing the environmental impact of these components throughout their life cycle. Also, this paper highlights the impact of design principles on End-of-Life Management of vehicles. As Design decisions of Component impacts up to 80% of emissions [1], it is important to focus on this phase for major contribution in reduction of emissions.

Carbon and rephosphorized pre-strained sheet steels for cold drawing forming operations were studied and the tensile, high cycle fatigue and fatigue crack propagation properties were determined. The fatigue limit was found to be higher for 20% than for 1% pre-strained condition. Threshold stress intensity factors (▵Ků) of 5.29 MPa. m1/2 for rephosphorized steel and 7.07 MPa. m1/2 for carbon steel. Critical crack lenghts were calculated by ▵Ků and fatigue limit data using the Lukas-Klesnil short-crack criterion. Through fractographic analysis it was possible to determine the general behavior of tested materials near threshold.

“Digital Prototype” simulations have been used at DaimlerChrysler to achieve vehicle level NVH objectives. The effectiveness of these simulations to guide the design when faced with vehicle parameter uncertainties is discussed. These uncertainties include, but are not limited to, material properties, material gauges, damping, structural geometry, loads, boundary conditions and weld integrity. Manufacturing and assembly processes introduce variations in the nominal values of these parameters resulting in a scatter of vehicle level NVH simulation responses. An example of a high frequency NVH concern will be studied and modified to arrive at robust design guidance when faced with uncertainty. The validity of a “deterministic digital prototype” simulation model and its relevant role as a “trend predictor” rather than “absolute predictor” tool in guiding the design is also discussed.

This paper presents the derivation of the equations for circumferential, longitudinal and radial heat transfer conductance for a thin shell toroid or a segment of the toroid. A thin shell toroid is one in which the radius to thickness ratio is greater than 10. The equations for the surface area of a toroid or of a toroidal segment will also be derived along with the equation to determine the location of the centroid. The surface area is needed to determine the radial conductance in the toroid or toroidal segment and the centroid is needed to determine the heat transfer center of the toroid or toroidal segment for circumferential and longitudinal conductance. These equations can be used to obtain more accurate results for conductive heat transfer in toroid which is a curved spacecraft components. A comparison will be made (1) using the equations derived in this paper which takes into account the curvature of the toroid (true geometry) and (2) using flat plates to simulate the toroid.

“DELRIN” is a new thermoplastic which offers high strength, excellent thermal stability, good fatigue life, low creep, and excellent solvent resistance. This paper describes the physical and chemical properties of the material, and the range of possible uses. The material is easily fabricated into complex shapes by standard injection-molding techniques. Also, it can be easily joined to itself or to other materials. The authors think that the material offers advantages over metals in its good fric-tional properties, abrasion resistance, and corrosion resistance.

The Boeing Company in Mesa, Arizona, has been conducting a concept design study of a roadable helicopter called the “Converticar” to assess its feasibility. This is a twin-engine vehicle with twin retractable coaxial counter-rotating rotors. The purpose of the study is to describe a vehicle that carries four passengers in the equivalent of a luxury car that also can fly like a helicopter, and can be priced like a luxury car. To come near this cost goal, the production rate must be on the order of 500,000 units a year. At that rate there is no chance of training a comparable number of pilots each year. So the machine must fly and navigate autonomously, with the pilot just dialing in where he/she wants to go. Technologically, the concept appears to be feasible. Modern design processes, new materials, and improved manufacturing process should allow the Converticar to be built at the prescribed rate when the proper infrastructure for manufacturing it is made available.

In one of the fatigue tests for wet friction materials, “bump test”, an inertia-type rig equipped with a multi-disk assembly is used. One of the steel disks in the assembly has radial bumps for the purpose of creating high local contact pressure and high temperature. Due to the severe contact conditions, a comparative testing for different friction materials can be conducted within a relatively small number of cycles. In the paper, a design of a “bump” assembly used for automotive wet friction materials is described. Based on both experimental tests and advanced contact modeling, non-uniform contact pressure generated by the bumps and resulting temperature are estimated. The computational model is used then to study the influence of the modulus of elasticity of the friction material and reaction plate thickness on the contact conditions. The bump fatigue tests lead ultimately to material failure.