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Material characterisation is fundamental to the effective design and analysis of elastomeric components; as a result many static test procedures and constitutive expressions have been developed over the years and subsequently used in Finite Element code. For many sealing applications quasi-static material properties have been used as an aid in design, typically for extreme and new structural configurations. Although it adequately captures the basic characteristics of a seal design it provides no information regarding the effects of dynamic excitation and how it affects the structural integrity of the seal. As a first order approximation interconversion relations were used to study dynamic effects on designs typically modeled with quasi-static material properties. Under dynamic loading it is possible for the contact force to fall below design tolerances.

Multi-layer steel (MLS) cylinder head gaskets are becoming more widely used to seal an engine. Therefore, it is important to understand the interaction between the engine head, block and head gasket. While experimental methods for determining necessary gasket tightening loads and experimental data relating some gasket design parameters to failure are available, it is very costly and time consuming. A numerical method, such as the finite element (FE) method, has proven to be very useful and efficient in aiding gasket design. A 3D engine FE analysis can predict a number of parameters. Of particular interest are the motion as well as the contact profile of the head, block and gasket. This information, usually difficult or impossible to obtain from a 2D FE analysis, can be used to predict the two most common failure modes of a gasket, fatigue crack and leakage.

It is generally believed that vinylidene fluoride (VF2) containing fluoroelastomers, such as di- or ter- polymers of VF2, hexafluoropropylene (HFP), and tetrafluoro-ethylene (TFE), exhibit better low temperature performance than non-VF2 containing fluoroelastomers, such as copolymers of TFE and propylene (P). However, it is found in this study that this is true only for original compounds. The advantage disappears once the compounds are aged. This study was carried out using a dynamic mechanical analyzer by measuring the temperature response of the elastomers before and after aging in a lubricant. Because of the relative inertness of TFE-P polymers to lubricant additives, it undergoes very little chemical change resulting in practically no change to its low temperature performance. On the other hand, VF2-containing polymers undergo significant chemical changes resulting in a degradation of their low temperature performance.