EOS M 400-4

The EOS M 400-4 is EOS's largest and most capable metal additive manufacturing system, combining a 400 x 400 x 400 mm build volume with four 400 W Yb-fiber lasers. Introduced as the flagship of the EOS metal portfolio, the M 400-4 is designed for industrial serial production of large, complex metal parts where both part size and build throughput are critical. The quad-laser, large-format combination makes it one of the most powerful LPBF systems available for aerospace, defense, energy, and heavy industrial applications.

The 400 mm square build plate enables components that are simply out of reach for mid-frame systems like the M 290. Large turbine blades, aerospace structural frames, industrial tooling, and large medical implants can be printed in their entirety rather than requiring segmentation and post-process joining. All four 400 W lasers operate simultaneously across the full build area with EOS's full-overlap architecture, meaning any laser can access any point on the build plate — eliminating the stitching artifacts and zone-boundary quality issues that compromise part integrity in zoned multi-laser systems.

The M 400-4 is built around EOS Industrial Production (EIP), an automated production ecosystem that integrates build job management, powder handling, system monitoring, and quality documentation into a unified factory workflow. The automated powder management system handles sieving, transport, and storage with minimal manual intervention, reducing operator contact with reactive metal powders and increasing overall machine utilization. EOSTATE Monitoring, including melt pool imaging and powder bed inspection, provides the layer-by-layer data required for aerospace and defense traceability.

Materials qualified for the M 400-4 include the full EOS metal library: titanium alloys (Ti6Al4V, Ti6Al4V ELI), nickel superalloys (IN718, IN625), aluminum alloys (AlSi10Mg, AlSi12), cobalt chrome, stainless steels (316L, 17-4PH), and maraging and tool steels. Build rates with four lasers are substantially higher than single-laser systems, though actual throughput depends heavily on part geometry, nesting density, and layer thickness. A new M 400-4 system is priced between $1,800,000 and $2,500,000 fully configured.