Random Fatigue Analysis of Automotive Bevel Gear

The most common mode of the gear failure is tooth breakage, which is usually produced by bending fatigue failure. It is important to manufacture the gears which can withstand the applied stresses in view of safety and economic requirements. In this study, fatigue test and analysis were performed to evaluate the bending fatigue strength of an automotive bevel gear. Test fixtures of the double tooth concept were considered to obtain reliable fatigue test results. Fatigue life of automotive bevel gear was evaluated by Weibull analysis. To compare the test results and to verify the fatigue analysis procedures, fatigue analyses were carried out. The results of fatigue analysis show that fatigue life and crack initiation sites were well agreed with test results. The random loading of bevel gear under the real driving conditions was defined here, and then the fatigue analysis under random loading was also performed.