Study of Improvement of the Build Rate of Ti-6Al-4V Alloy by Laser Beam Powder Bed Fusion Technology

Abstract

Metal powder bed fusion additive manufacturing technologies are increasingly being adopted in industrial applications, but their widespread implementation on an industrial scale is hindered by the high manufacturing cost. This study investigates two strategies to improve the build rate of Ti-6Al-4V alloy processed by powder bed fusion using a laser beam (PBF-LB/Ti6Al4V), which is a critical factor that affects the cost of an additive manufacturing part. The first strategy involves increasing the layer thickness from 30 µm to 60 µm, while the second strategy entails increasing the particle size of the raw material from 25-45 µm to 45-106 µm while maintaining a layer thickness of 60 µm.The experiment involved modifying the process parameters based on the energy density (J/mm2), combining laser powers between 180-470 W, scanning speeds between 600-2611 mm/s, and distance between passes from 0.12 to 0.21 mm. With the highest density level process parameter combinations, a comparative study of manufacturing times for a given geometry showed a productivity improvement of up to 50%. The static mechanical properties of the specimens were evaluated by performing tensile tests. The roughness of the melt was determined for each strategy. The study concludes that modification of process parameters can reduce the build rate of PBF-LB/Ti6Al4V while maintaining its tensile strength and surface roughness.