High-damping Lightweight Design for Laser Powder Bed Fusion 20MnCr5 Gears

Abstract

Copyright © (2025) by American Gear Manufacturers Association. All rights reserved.The increasing demand for sustainability and e-drive transmissions is reshaping the gear industry, requiring mitigation of Noise, Vibration and Harshness (NVH). In this scenario Laser Powder Bed Fusion (L-PBF) is a promising additive manufacturing technology offering design freedom while maintaining a mechanical behavior suitable for gear application. Despite the capabilities of AM, there remains a gap in systematically applying its design freedom to enhance the vibration behavior of gears. This study proposes a method that takes advantage of the design freedom of L-PBF to enhance the damping behavior of a pinion gear while simultaneously reducing its mass. The proposed method reduces the component's weight by topology optimization, while simultaneously, the topology optimization is calibrated to ensure that stiffness modifications resulting from the structural changes enhance NVH characteristics by improving component's damping. Additionally, the method incorporates transmission error simulations, enabling informed design decisions that help avoid resonance frequencies. Applying this method resulted in approximately 22% reduction in gear weight and a substantial improvement in damping properties. Moreover, the stiffness modifications adjusted the transmission error pattern, effectively avoiding critical frequencies. The method supports the development of advanced and sustainable gear systems tailored to the future demands of electromobility.