This work explores how surface roughness in Inconel 718 (IN718) cooling channels—commonly used in high-temperature aerospace environments—can be intentionally tailored through process development to optimize fluid dynamic performance. Through a combination of experimental manufacturing, post-processing, and cold flow testing, the correlation between roughness metrics (e.g., Sa) and the pressure drop experienced under realistic flow conditions is investigated.
Surface roughness is quantitatively measured using high-resolution 3D profilometry, and the pressure drop is evaluated through nitrogen or water-based cold flow tests. The results show how specific roughness regimes can be used to steer pressure losses, allowing for functional design decisions during the AM process chain—either to minimize flow resistance for higher cooling efficiency or to intentionally increase it in areas requiring enhanced mixing or control.
This study supports the growing need for design-for-AM strategies that align process parameters with performance targets, enabling smarter and more efficient propulsion components for next-generation launch systems.
Speaker: Maximilian Strixner, Senior AM Engineer, The Exploration Company