Reverse engineering: a conceptual study of fatigue failure for gear application / Mohd Amin Nurdin

Fatigue failure contributes a large percentage of gear failure. Fatigue failure is known as a sudden and catastrophic separation of a machine part into two or more pieces as a result of the application of fluctuating loads or deformations over a period of time. In daily applications, a gear system will experienced this kind of failure mode since its applications involved loading and unloading loads for a period of time. Basically, in gear system, the point of concentration for fatigue is at its root. However, it is difficult but not impossible to investigate the fatigue behavior at the root. For this study, two materials that differ in their materials compositions were prepared for fatigue analysis, since analyzing a root of gear teeth has a difficulty. Also a construction of a gear model was performed by using CATIA and MITcalc software. As an experimental validation for fatigue analysis, a series of loads is applied to the specimens. This method represents a better way in analyzing crack propagation on the material's surface until it is fractured. At microscopic level, propagation of crack until fracture can easily be seen. For this study, this is a critical part, since the different in material compositions contributed to the different type of crack propagation. At this stage, any minor difference must be taken since it brings a lot of contributions to the analysis. Based on the result of this study, it is expected to achieve a deep understanding on how the crack propagates on two different kinds of materials.