A simulation study to systematically evaluate the effects by design modifications in a complex gear geometry on distortion behavior

In response to economic and ecological demands, weight reduction has become a paramount objective in the automotive industry, driving innovation in materials and component design for lightweight construction. However, achieving lightweight components without compromising production feasibility presents challenges. The process of heat treatment, aimed at enhancing material properties, introduces size and shape alterations, alongside residual stresses, which can impact subsequent manufacturing and component longevity. Understanding the mechanisms behind these changes is crucial for cost-effective design and post-processing. While in-situ measurement techniques are limited in heat treatment facilities, simulation software offers a viable alternative for studying dimensional alterations. Despite recent advancements in simulation tools, the complexity of heat treatment processes demands comprehensive material parameters and boundary conditions, often making computations time-consuming. While existing simulations primarily focus on process optimization and property enhancement, research into the impact of geometric variations on final distortion behavior remains limited. This study aims to bridge this gap by investigating the influence of geometric variations on distortion behavior through heat treatment simulation, contributing to a deeper understanding of lightweight component design optimization. In preparation for the numerical investigations, extensive work was carried out to determine the temperature- and location-dependent heat transfer coefficient (HTC) and the conversion behavior. Extensive calibration and validation work was also carried out. In the numerical area, cyclical boundary conditions were programmed for 3D simulation of the gear. After partial validation, this model was used in close combination with experimental work to evaluate the compensation potential of modified cross-sectional transitions. Ultimately, the model was used to gain a deeper understanding of the complex interplay of geometry, thermal and transformation-induced strains.