Effect of nanoparticle additivation on the microstructure and microhardness of oxide dispersion strengthened steels produced by laser powder bed fusion and directed energy deposition

In this contribution, the effect of nanoparticle additivation on the microstructure and microhardness of oxide dispersion strengthened steels (ODS) manufactured by laser powder bed fusion (L-PBF) and directed energy deposition (DED) additive manufacturing (AM) is studied. The powder composites are made of micrometer-sized iron-chromium-alloy based powder which are homogenously decorated with Y2O3 nanoparticles synthesized by pulsed laser fragmentation in water. Consolidated by L-PBF and DED, an enhanced microhardness of the AM-built ODS sample is found. This increase is related to the significant microstructural differences found between the differently processed samples.