Powder maker TANIOBIS has processed two niobium alloys, C-103 and FS-85, by laser powder bed fusion on a four-laser EOS AM500Q, after developing parameters on a single-laser AM400. Parts reached porosity below 0.1% and optical density above 99.9%, and demonstrator rocket engine nozzles 53 mm in diameter and 100 mm tall came off the plate crack-free. The work targets engines and hypersonic hardware running past 1,050°C, where nickel superalloys start to soften and niobium’s 2,477°C melting point takes over.
To check consistency on the larger machine, the team built 52 cubes scattered randomly across the plate using four parameter sets; porosity stayed under 0.3% throughout, with a few outliers blamed on spatter. The C-103 process window widened to 95-255 J/mm³ on the AM500Q, versus 160-240 J/mm³ found earlier on the AM400. FS-85 needed a tighter window, 105-125 J/mm³.
| Property | C-103 | FS-85 |
|---|---|---|
| Tensile strength (RT) | 565 MPa | 750 MPa |
| Young’s modulus | 95 GPa | 137 GPa |
| Elongation | 20-22% | 6-7% |
| Tensile strength at 1,500°C | near zero | ~220 MPa |
Heat treatment lifted elongation in both alloys to about 30% with little strength loss. Printed C-103 beat rolled C-103 at elevated temperature, 557 MPa versus 420 MPa tensile at an unspecified test point, though the gap narrowed above roughly 800°C as the printed grain structure coarsened. EBSD showed printed parts carry elongated, build-direction grains rather than the uniform ~24 µm grains of rolled stock, which is why bars cut along the build axis (XZ) were less ductile than transverse (XY) bars. Full recrystallization after two hours at 1,900°C needed temperatures well past 0.6 of the melting point, which the team attributes to the absence of prior deformation and higher oxygen content than rolled material.
Tensile bars from the AM400 and AM500Q matched closely; strength from the four-laser system came in slightly lower, which researchers trace to reduced residual stress from continuous multi-laser operation. TANIOBIS has also signed Elmet Technologies to distribute the two powders in North America, as competing qualification efforts proceed on Elmet’s own 3D Systems DMP Flex 350 Triple and on Velo3D’s Sapphire printers with Amaero’s C-103 powder.