Characterisation of the effect of powder reuse on extra low interstitial Ti-6Al-4V powder in laser-beam powder bed fusion manufacturing

Quantification of the impact of powder recovery and reuse on powder quality during laser-beam powder bed fusion (PBF-LB) is an essential milestone to enable the large-scale industrial adoption of PBF-LB. This study investigates the influence of powder reuse for a single full load of Ti-6Al-4V powder in an industrial-grade PBF machine with automatic powder and waste handling. Powder properties investigated include particle size distribution, flow and density analysis in accordance with international standards. The chemical composition of both powder and as-printed components is determined to quantify any evolution in powder properties through successive cycles of recovery and reuse. After a full load of powder was consumed, all powder properties remained stable. PBF-LB caused an increase in as-printed interstitial chemistry, but did not exceed the ASTM Grade 23 limit. This confirms a safe operating window for powder reuse without a reduction in quality of industrial components.