Using single pulses in powder-blown directed energy deposition to fabricate high-aspect-ratio metal pins

This study investigates the fabrication of high-aspect-ratio metal pins using powder-blown directed energy deposition. Pins are deposited by consecutive laser pulses using titanium alloy Ti6Al4V as feedstock material. A physics-integrated experimental-analytical-numerical framework is developed to predict pin geometry, pin growth and thermal history during fabrication. The framework combines experimental in-situ temperature measurements, an analytical geometry model, and a finite element thermal model for melt pool lifetime predictions. Results show good agreement between model predictions and experimental observations, enabling controlled constant-diameter vertical pin growth with optimised process parameters, which is crucial for applications such as hybrid metal-composite joining and structural repair.