Laser Powder Bed Fusion of Chromium Bronze Using Recycled Powder

Laser powder bed fusion (LPBF) of Cu-0.5Cr was carried out using recycled powder taken out from the LPBF machine after previous printing. Various volumetric defects characterized the powder wherein particle size distribution was the same as virgin powder. Using recycled powder resulted in extra spherical pore formation after the LPBF process. Despite that, a relative density of 99.2% was achieved by LPBF parameters optimization. Solidified microstructure with a small volume of defects consisted of an oversaturated dendritic Cu matrix and nano-sized Cr precipitations providing strengthening mechanism occurrence. The possibility of a satisfactory level of mechanical properties with sigma(0.2) = 136.8 MPa, UTS = 187.4 MPa, along with 15.5% of elongation achieving, was shown.

Automated summary

By utilizing recycled powder in the laser powder bed fusion process, despite the formation of extra spherical pores, a relative density of 99.2% was achieved through optimization of LPBF parameters. The solidified microstructure exhibited a small volume of defects, consisting of an oversaturated dendritic Cu matrix and nano-sized Cr precipitations to provide strengthening mechanisms, resulting in satisfactory mechanical properties such as sigma(0.2) = 136.8 MPa, UTS = 187.4 MPa, and 15.5% elongation.