Work

Development and Experimental Validation of a Flow-Optimized, Additively Manufactured, Highly Integrated Powder Nozzle for Internal Laser Cladding

Year: 2026

Type: article

Abstract: Internal laser cladding is applied for the repair and functionalization of components with internal geometries such as tubes and bores. However, the confined geometry imposes strong constraints on nozzle size, powder delivery, and thermal stability, making reliable coating of small inner diameters challenging. This study presents the development and validation of a compact powder nozzle for internal laser cladding manufactured by laser powder bed fusion (PBF-LB/M) from a precipitation-hardenable copper–beryllium alloy. The nozzle design was optimized using coupled computational fluid dynamics (CFD) and discrete element method (DEM) simulations to analyze gas flow and powder particle dynamics. Prototypes were experimentally characterized with respect to powder stream geometry using a light-sheet imaging method and were additionally subjected to thermal load tests to evaluate the cooling performance. The results showed that the integrated water-cooling system dissipates sufficient heat to prevent a measurable temperature increase of the nozzle, even under worst-case irradiation conditions. Finally, internal laser cladding experiments in a tube with a diameter of 65 mm confirmed stable powder delivery and uniform Inconel 625 coatings. The results demonstrate the potential of additively manufactured copper-based nozzle designs with integrated cooling for reliable laser cladding in confined internal geometries.

Source: Procedia CIRP

DOI: 10.1016/j.procir.2026.07.018