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Silicone-based RTV sealants see widespread use in the automotive industry. In the uncured state, RTV silicone has the consistency of thick toothpaste and can be easily applied to form an effective seal. However, a significant amount of anecdotal evidence suggests issues exist with RTV’s ability to maintain a satisfactory seal in some long-term engine sealing applications. ASTM D7216 is used to evaluate the effects of different oil blends on a set of standard molded reference samples after submersion in an elevated temperature oil bath. The evaluated material properties are hardness, percent volume change, tensile strength, and ultimate elongation. A library of such results is readily available through Savant Laboratories of Midland, Michigan. Given RTV’s widespread use, surprisingly no such library of information exists concerning an engine oil’s effects on different RTVs.

In order to enhance the ability of engineers to quickly and easily evaluate new heat shield materials and construction methods for the underhood and underbody regions of the vehicle, a standardized rig test is being developed. The issues involved in the development of this test method are discussed as well as the important parameters. Test results for different heat shield materials are also presented.

The use of ceramic fiber in friction applications is presently a relatively small market. However, based on the market need for a high temperature reinforcing material the use of ceramic fibers should grow rapidly, specially in the more demanding applications. In the study presented here, the effect of various fiber characteristics of ceramic fiber will be evaluated in a simple formulation for frictional and mechanical properties. The particular fiber characteristics evaluated are fiber dimensions, fiber surface and amount of non-fibrous material. A comparison between ceramic fiber, glass fiber and PMF will also be presented to show the relative level of performance of the three competitive materials.