Speaker
Description
Laser Powder Bed Fusion (L-PBF) is widely used to manufacture complex metallic components. However, low-angle overhang features generally require support structures to prevent distortion and build failure. Conventional contact supports provide mechanical and thermal assistance during the manufacturing process. However, they must be removed after manufacturing, which increases post-processing time and cost. In addition, support removal often leaves support marks on the part surface and can cause surface damage. In this study, a topology-optimized non-contact support strategy is proposed for Ti-6Al-4V L-PBF to improve overhang quality while reducing support-induced post-processing issues and avoiding direct metallurgical bonding between the part and the support. The proposed approach introduces a thin unmelted powder gap between the overhang and the support structure. Thermal analysis was first performed to evaluate the temperature history and thermal loading conditions of overhang specimens with different inclination angles. Based on the thermal analysis results, topology optimization was conducted to design a support geometry that enhances heat transfer from the overhang region to the base plate. The optimized support geometry was then evaluated using build simulation to verify that thermally induced deformation of the support did not cause interference with the part during manufacturing. The dimensional accuracy of the manufactured specimens was evaluated using 3D scanning. The optimized non-contact support was compared with basic non-contact support, basic contact support, and unsupported overhang conditions. At a 25° overhang angle, the optimized non-contact support reduced the upper free-end RMS displacement by 45.7% compared with the basic non-contact support. The lower free-end RMS displacement was also reduced by 86.2% compared with the basic contact support at 25°. At a 20° overhang angle, the optimized non-contact support reduced the lower free-end RMS displacement by 93.9% compared with the unsupported condition. The optimized non-contact support also retained the overhang geometry at 15°, indicating improved stability for low-angle overhang manufacturing. These results demonstrate that topology-optimized non-contact supports can provide effective thermal assistance without direct bonding to the part. The proposed strategy offers a design approach for improving dimensional stability and reducing support-induced damage in Ti-6Al-4V L-PBF overhang structures
| Speaker Country | Republic of Korea |
|---|---|
| Would you like to publish your paper in the special issue of BHM "Berg- und Hüttenmännische Monatshefte" | No |