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Considered in this study by the use of finite element model is a unit of assembled stator and one-way clutch (OWC) housed in a test setup, where the inner chamber is maintained at a given elevated temperature while its exterior housing surfaces are exposed to the room temperature. The two key components of dissimilar metals are assembled through the conventional interference fitting at their interface surfaces to form a friction joint at the room temperature. Due to the difference in the thermal expansion coefficients of two dissimilar materials, the outer component of aluminum from this joint tends to expand more than the inner component of steel when the temperature rises, thus leading to a possible relaxation in joining connection at their interface.

Engineers have been interested in a thorough understanding of how a case-hardened part, consisting of soft substrate (or core) and hard surface, behaves under various types of loads, ranging from extremely destructive load to mild cyclic loads. The use of numeric simulation, such as well known finite element method, has made it much easier to achieve this. Throughout this investigation, the author proposes a methodology to treat such a case-hardened part as multi-laminated metal with a relative thin outer layer whose ultimate tensile strength may be several times as high as its inside core material. In the case studies to demonstrate the technique, a representative automotive component is subject to various loads due to not only the inertia of its own but also that imparted from heavy springs housed within it. A comparison was made between two approaches to account for the hardness transition between the hard layer and soft core.

Metal fatigue has been a topic interesting to engineers for long, because it has had a profound impact on making the design of virtually all products more reliable. As the research in this area evolved, the understanding of fatigue has been gained so tremendously that it has been become possible to conduct more and more complicated fatigue analysis or simulation without having to undergo lengthy fatigue tests for a product under design. In this work is a numerical model to predict the fatigue life of a power train component, whose metal material essentially behaves as being inhomogeneous due to a thin and hard surface layer on the top of the base material. As a typical case in the power train of automobiles, the clutch component is subject to the inertial load arising from an angular velocity as well as the torque loads, varying cyclically with time in a form other than what is called constant-amplitude.

Presented here is the finite element modeling of plate-structures within which mechanical properties varied dramatically from their outer surfaces towards inside cores. Developing such a model representing what can be characterized as laminates is of great significance in accurately predicting the strength. The benefits of this proposed methodology will be discussed by case studies of a centrifugal pendulum that has gained its popularity in high-end passenger cars because of its superior vibration suppression. The system in this work is subject to an excessive and destructive load due to centrifugal forces at extremely high angular velocities. It can be shown that the inner core, with much softer mechanical properties, easily gets into the plastic state and significantly restrains it from continuing to carry more loads as the angular velocity is ramped up. Consequently, the outer layers have to take an increased share of loads and their stresses are significantly raised.