Continuous Coaxial Nozzle Design for LMD based on Numerical Simulation

Abstract

The LMD technology is becoming one of the most important emerging manufacturing technologies in the modern industry, due to its benefits when building-up geometries, repairing damaged parts or the creation of coatings to improve material properties and behaviour. One of the most relevant parameters in LMD process is the efficiency of the trapped powder into the melt pool, since metallic material powders use to be very expensive. With the aim of improving the ratio between the trapped powder in the deposited area and the total injected powder, the work presents a new methodology for continuous coaxial nozzle design for the LMD process based on a complete CFD model. The numerical model can predict particle flow, speed, powder concentration, etc. and design can be optimized using this input data. The model has been validated and then, it has been used for the design of two different nozzles: one discrete and one continuous coaxial nozzle.