The launch of a broadband satellite failed due to a structural flaw in its 3D-printed titanium lattice. Digitized ultrasound analysis revealed that critical struts were incomplete. The cause was an error in nTopology's slicing software, which generated fatal stress concentrations under launch vibrations. This case underscores the need to validate every layer of a generative structure before final manufacturing. 🛰️
Forensic Analysis: From nTopology to GOM Inspect and Siemens NX 🔍
Generative design in nTopology optimized the lattice for maximum stiffness and minimum weight, but an artifact in the slicing post-processing omitted sections of the diagonal struts. GOM Inspect digitized the failed part and detected the discontinuities through direct comparison with the nominal CAD model. With this data, Siemens NX Additive simulated the fatigue of Ti-6Al-4V titanium under the launch load profile. The results showed that the incomplete struts acted as notches, reducing fatigue life by 60% and causing brittle fracture during the second acceleration stage.
Lessons for Validating Printed Lattices ⚙️
A slicing error is invisible to traditional mechanical tests if the actual part is not replicated. The solution is to integrate a high-resolution 3D scan (such as GOM Inspect) as a mandatory post-printing step, followed by a fatigue simulation in Siemens NX that uses the actual scanned mesh, not the ideal one. Only then are missing struts or internal porosities detected. For critical structures, I recommend a finite element analysis with the as-built geometry before any flight integration.
What slicing parameters and fatigue simulation strategies do you consider critical for predicting failure in 3D-printed titanium lattices, given that in the satellite case the slicing error was the trigger for the structural collapse?
(PS: Material fatigue is like yours after 10 hours of simulation.)