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The objective of this work is to test and develop monotonic tensile properties and strain controlled fatigue properties of a cast ductile iron. The test data and the related material constants will be used in conjunction with vehicle loading data to perform finite element stress-strain analysis and fatigue life prediction analysis to aid in the design of automotive components made from ductile iron. Currently, such material property data does not exist in the literature for this particular grade of ductile iron. Monotonic tension and fully reversed strain controlled fatigue tests were conducted by following ASTM E-8, ASTM E-606, and SAE J-1099 on samples machined from the cast ductile iron. Monotonic tensile properties were obtained, including Young's modulus, yield strength, ultimate tensile strength, elongation, reduction in area, strength coefficient K, and strain hardening exponent n.

Shaft surface texture plays a very important role in rotary oil seal system performance. Functionally, the shaft surface has to prevent oil leakage via pumping between the shaft and seal. The shaft surface texture must also provide adequate contact with the seal lip, while maintaining a lubricant film. Furthermore, the initial surface texture of the shaft plays a vital role in the process of oil seal lip break-in. The shaft surface finish specification is typically Ra, 10 to 20 μ″ with a 0° ± 0.05°lead angle. The paper will describe a new surface measurement method based on interference microscopy, which generates a visual representation of a significant portion of the shaft surface texture to allow direct lead angle detection. Using this new technique, this paper will demonstrate the heredity of lead generation. The shaft 3D surface texture measurement also provides a measure of the surface volume available for lubricant retention.