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3D Bioplotter Research Papers
Ink-Extrusion 3D Printing and Silicide Coating of HfNbTaTiZr Refractory High-Entropy Alloy for Extreme Temperature Applications
An oxygen-resistant refractory high-entropy alloy is synthesized in microlattice or bulk form by 3D ink-extrusion printing, interdiffusion, and silicide coating. Additive manufacturing of equiatomic HfNbTaTiZr is implemented by extruding inks containing hydride powders, de-binding under H2, and sintering under vacuum. The sequential decomposition of hydride powders (HfH2+NbH+TaH0.5+TiH2+ZrH2) is followed by in situ X-ray diffraction. Upon sintering at 1400 °C for 18 h, a nearly fully densified, equiatomic HfNbTaTiZr alloy is synthesized; on slow cooling, both α-HCP and β-BCC phases are formed, but on quenching, a metastable single β-BCC phase is obtained. Printed and sintered HfNbTaTiZr alloys with ≈1 wt.% O shows excellent mechanical properties…