1. Introduction
Topology optimisation routinely produces organic geometries that are difficult or impossible to manufacture with subtractive or casting processes, but laser powder bed fusion removes many of these constraints while introducing new ones related to overhanging surfaces and thermal residual stress.
2. Methodology
A suspension bracket subject to combined bending and torsional loads was optimised using the Solid Isotropic Material with Penalisation (SIMP) method with an added overhang-angle penalty term constraining unsupported surfaces to angles greater than 45 degrees from horizontal. The optimised geometry was printed in Ti-6Al-4V via laser powder bed fusion and tested under quasi-static loading.
3. Results
The optimised bracket achieved a 41 percent mass reduction relative to the baseline cast aluminium design while maintaining a factor of safety of 2.7 under the design load case, and required zero support structures during printing, eliminating post-processing time associated with support removal.
4. Conclusion
Embedding manufacturing constraints directly within the optimisation loop yields lightweight, print-ready components without iterative manual redesign. Future work will extend the constraint set to include fatigue-driven objectives.
References
[1] Bendsoe M. P. and Sigmund O., Topology Optimization: Theory, Methods and Applications, Springer, 2003. [2] Langelaar M., Topology optimization for additive manufacturing, Structural and Multidisciplinary Optimization, 2017. [3] Gibson I. et al., Additive Manufacturing Technologies, Springer, 2015.