Analysis and Fowability of β Type Ti-15Mo-5Zr-3Al Alloy Powders for Laser and Electron Beam Powder Bed Fusion Methods

Abstract

Although gas atomization technique for additive manufacturing is highly developed, differences of metallic powder properties between for laser powder bed fusion （L-PBF） and for electron beam powder bed fusion （EB-PBF） yet to be addressed systematically. This study aimed to analyze the properties and functions of atomized powders for L-PBF and EB-PBF and compare them. Gas atomized powders showed spherical shape regardless of their size, indicating no relation of cooling rate to powder shape. Relatively large size of EB-PBF powders （D₅₀ = 83.3 μm） with sharp size distribution （D₉₀/D₁₀ = 1.90） showed high flowability compared with L-PBF powders （D₅₀ = 31.4 μm） with broad size distribution （D₉₀/D₁₀ = 3.02）, whereas the difference in laser absorption was not shown. These findings obtained here demonstrated that the powder flowability, which determines the quality of powder bed, can be tightly related with powder propert ies in gas-atomized metallic powders.