A Thermo-Structural Finite Element Analysis for Relaxation of Interference Fit at an Elevated Temperature

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. In this work, through a finite element model of assembling stator and outer race in a bulky test fixture, it will be demonstrated that the relaxation of joint formed by the interference fitting will also largely depends on how the outer component of aluminum interacts with the fixture at the elevated temperature.