Shaft parts have great demands especially in the automotive industry and are manufactured by various processing routes depending on the requirements. Joining-by-forming is receiving increasing attention as a cost-effective production method for the shaft parts with complex geometries. The authors have investigated the mechanical joining process that a knurled shaft and a holed disc are rotationally locked by forming. This joint showed higher torsional strength than the conventional spline-fit joint. However, application of this joining process is limited because of no active locking in the axial direction. In this study, improvement of the axial strength for the current process is aimed by adding a groove and a step to the knurled shaft. Indenting depth of the stepped portion is crucial to the performance of the joint and its effects on the joining force, axial joining strength and dimensional accuracy are clarified by using a steel shaft and an aluminum disc. The results of push-out tests and torsional tests for the joint suggest that the revised process brings sufficient joining strength both in the radial and axial directions.
Hirota, K., Kitamura, K., Ukai, Y., & Matsunaga, K. (2017). Mechanical joining of shaft and holed disc in rotational and axial directions. In Procedia Engineering (Vol. 207, pp. 980–985). Elsevier Ltd. https://doi.org/10.1016/j.proeng.2017.10.862