This paper deals with the residual stress depth profiles in case-carburized gears, their effects on the fatigue behavior as well as the enhancement of ISO/TS 6336-4 to include the consideration of tensile residual stresses in the tooth core area. For this purpose, an equation is also presented with which these tensile residual stresses can be estimated so that they can be used in the enhanced evaluation of TFF risk.

This report discusses grain size and its influence on metallurgical properties including its effect on yield strength, ultimate strength, fatigue strength, and fracture toughness. Also discussed are manufacturing issues such as heat treatment, hardenability, and machinability. 

Bevel gears are widely used in various industrial applications, such as automotive, aerospace, and marine industries, due to their ability to transfer power between non-parallel shafts. The conventional manufacturing of bevel gears involves several time-consuming and costly processes, including gear blank preparation, gear cutting, and gear finishing. The increasing demands on gear components regarding increasing power density, reducing installation space, reducing weight, and increasing efficiency are also reflected in the design of gear components. The reduction of installation space and weight as well as the increase in power density often leads to an optimized wheel body design that interacts with the gearing in terms of load capacity and stiffness. This leads to an increase in the required geometric degrees of freedom (DOFs). Due to the resulting complex wheel body shapes and different production-related effects, production-related geometry adjustments may also be necessary. Tools for evaluating the gearing in combination with the wheel body shape and its influences nowadays form the basis for unlocking the holistic optimization potential of transmission components.