Materialise Engineer Spotlights KU Leuven Study Using Second LPBF Laser to Locally Control Duplex Steel Microstructure

KU Leuven researchers demonstrated in-situ microstructure control during laser powder bed fusion builds by repurposing the second beam in multi-laser LPBF systems, rather than adding it purely for throughput. Targeting duplex and super duplex stainless steels, whose corrosion resistance depends on a near-equal ferrite-austenite balance that LPBF's rapid cooling normally suppresses into a brittle, mostly ferritic structure, the team used the additional laser to locally adjust thermal history and phase fractions within a single build. The work was detailed by Michele Pavan, Materialise's Research Engineering Manager, writing for 3D Printing Industry.

Furnace heat treatment has been the only practical fix for duplex alloy microstructure, but it adds cost, time and distortion risk while only ever delivering a uniform result across the whole part. For Materialise, whose business rests on software and qualified-part production services rather than machine building, tracking and interpreting this kind of process research supports its role advising industrial customers on DfAM and qualification pathways for demanding alloys used in oil and gas, chemical processing and marine equipment. The practical takeaway is that multi-laser hardware already installed for throughput could become a metallurgical design tool, though the demonstration so far is confined to duplex stainless steel and has not been shown across other alloy systems.