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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.

Using rivets to join the metal parts has always been commonplace, not only in aerospace but also in automotive industries. In order to have a rivet joint work properly upon assembly, It is a common practice that the rivet shank has to be radially expanded and fit tightly with the holes of the jointed components, under a great amount of pressing loads on it. When the stiffness around these holes is insufficient due probably to the design limitation, the deformation may be severe enough to induce high stresses on them. It is very beneficial to use numeric methods to simulate the riveting process and predict whether a rivet joint will be sustainable in the manufacturing process. In this work, analyzed is a specific type of riveted assembly in which its rivet hole is at the close proximity to the edge of plate. In addition, the material characteristics for the riveted plates with case hardening are accounted for by modeling them as bi-layered structures.

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.

Vibration from a mechanical system not only produces unwanted noises annoying to people around, but also runs a risk of fatigue failure that would actually hinder its functionality. There are several forms of vibration depending on the sources of excitation forms. Mechanical systems with rotating components can be subjected to sinusoidal excitation due to the fact the center of mass is not perfectly aligned with the rotating axis. If the rotating speed is strictly ramping up or ramping down, this can create an excitation whose frequency is changing with time in a frequency range corresponding to the speeds swept. Compared with a single sinusoidal excitation, the issue with fatigue at swept sinusoidal excitation, is that as it sweeps through a wide frequency range, some swept frequencies will definitely coincide with the natural frequencies of the system. Certainly, the stress response exactly at the resonant frequency becomes the highest and could account for a lot of fatigue damage.