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Foaming of lubricating oil during operation of any automotive mechanism is undesirable. To control this problem, anti-foaming additives are often part of the formulated oil. However, during use, the oil contacts the gasketing material used to seal the mechanism and may extract pro-foamants in sufficient quantity to overwhelm the anti-foamant additive. Recognition of this problem has led to several different in-house tests of oil/gasket compatibility seemingly giving divergent information and technical direction concerning correction of foam-inducing factors of both the oil and gasket. It seemed appropriate to investigate and quantify the relative importance of several of the presumed influences on oil/gasket interaction. To do this, a relatively simple test simulating oil/gasket contact in the operating mechanism has been developed around an air foam-bath and applied in a series of Taguchi matrix studies to determine the influential factors.

The economic viability of PEM Fuel Cells for transportation uses requires significant reduction in the cost of assembling and sealing the PEM stack. Additionally the stack sealing system or method must last the life of the stack, is often used to enhance the structural strength of the stack and provide performance-enhancing functionality. This paper discusses PEM fuel cell stack sealing manufacturing and assembly methods. Methods examined include; die-cut gaskets, fabricated press in-place, insert molded designed profile, dispensed and other advanced sealing concepts. Economic comparison utilizing a value in place analysis takes into consideration seal assembly and stack fabrication methods in addition to seal material and processing costs. This analysis yields a method for rational selection of the best sealing method to be employed for the stack design and production volumes being considered.

Today one of the key issues facing electronic systems designs is heat dissipation. This is even more critical in Automotive Electronics because smaller and lighter modules coupled with higher component density lead to increased necessity of thermal power dissipation. Electronic modules with greater functionality and power also generate more heat. Higher temperatures can directly affect the performance and reliability of these modules. The unique properties of silicone thermal interface materials - in the form of adhesives, gels, encapsulants, gap fillers and thermal pads - can help automotive engineers get increased heat dissipation with higher levels of flexibility and better physical and electrical performance.

Heat dissipation is one of the key issues facing automotive engineers, as performance, reliability and longevity of electronic devices have all been shown to be directly affected by temperature. The current thermal challenges are unprecedented, as smaller engine compartments and higher component density raise under-hood temperatures, while electronic devices with greater functionality and power also generate more heat than previous designs. The unique properties of silicone thermal interface materials can help achieve higher levels of physical and electrical performance in automotive electronics -- facilitating heat dissipation in a variety of forms, including adhesives, gels, encapsulants, gap fillers, fabricated pads and phase change materials.

This paper provides a quantitative measurement of the reduction of permeation of hydrocarbons through Dimethyl (VMQ) and Fluorosilicone rubber (FVMQ) as a function of the degree of compression. Permeation testing was performed on five formulations at various compression levels. Finite element analysis (FEA) was utilized to relate the total hydrocarbon loss to the stress state in the gasket (specifically the hydrostatic pressure). It is expected that this relationship will be used to assist in the design and evaluation of the performance of a variety of gasket configurations. Interestingly, even moderate compression levels greatly enhanced the permeation resistance of the seals. Basing material selection for permeation resistance only on flat disk permeation cup data may be inappropriate. Ideally this new information will assist the seal designer to find ways to optimize the permeation performance of the gasket without the need to resort to testing every design option.