Trajectory planning and experimental research on robot-assisted laser machining of face gear surface microstructure

Abstract

• Robot-assisted laser machining microstructure method is first proposed. • A trajectory planning method based on defocus control is proposed. • The machined surface shows residual compressive stress. • The surface exhibits superoleophilic properties under the optimal parameter combination. Face gears play a crucial role in power transmission, making their service performance a key area of research in manufacturing. One approach to improving performance is machining microstructures onto the gear surface. This study proposes a robot-assisted laser machining method based on the surface microstructure of face gears. Considering the characteristics of laser defocus, a trajectory planning method based on defocus control is presented and verified. The influence of different process parameters on the surface morphology, residual stress, and wettability of the machined tooth surface is analyzed. Results demonstrate that the ablation width and depth increased with laser power. As the laser frequency increased, the ablation width and depth decreased. Additionally, the surface residual compressive stress caused by mechanical stress was greater than the residual tensile stress induced by thermal stress, resulting in a compressive stress state on the sample surface. Under the optimal processing parameters, the contact angle of the machined surface was 3.332°, indicating super-oleophilicity. These findings confirm that the robot-assisted laser machining microstructure method can achieve microstructural processing of the face gear surface, improve its wettability, and provide a reliable processing method to improve the service performance.