Two new designs of powder nozzles for Laser DED applications have been designed within the framework of the COAX project. The project, titled “Development of two new families of DED heads for their application in laser application processes of high reactivity materials and multi-material coatings” and reference Ref. PDC2021-121042-I00, is founded by the Spanish Ministry of Science and Innovation.
The researchers of the Dept. of Mechanical Engineering of the University of the Basque Country have designed two new nozzles for Laser powder Direct Energy Deposition (L-DED), a popular additive manufacturing technique. L-DED involves the use of a laser to melt and fuse metallic or ceramic powders into solid shapes, layer by layer.
The first nozzle is designed for use with titanium and highly reactive alloys, which are notoriously difficult to work with due to their tendency to react with the oxygen in the atmosphere and form brittle intermetallic compounds. The new nozzle introduces an additional inert gas flow that reduces the risk of oxidation and contamination during the L-DED process.
The second nozzle is designed for use with ceramic materials and for multi-material coating applications, which are becoming increasingly popular in fields such as aerospace, automotive and tooling industries due to their high hardness and thermal resistance. The new nozzle features a specifically designed geometry that allows for precise control of the focal distance of the powders of materials with differing density, resulting in smoother and more uniform mixing of multi-material powder flows.
Both designs have been obtained with the aid of CFD numerical simulations developed throughout the project. The model considers the combination of gas flows, injection of powder particles with a defined particle size distribution and, atmospheres of different gases.
New powder nozzle designs for highly reactive materials and multi-material coatings
