Additive manufacturing of magnesium–zinc–zirconium (ZK) alloys via capillary-mediated binderless three-dimensional printing

Several challenges are involved in employing fusion-based additive manufacturing (AM) technologies for magnesium (Mg) alloys. In this study, a novel 3D printing (3DP) technique was used to additively manufacture a green component made of Mg-5.9Zn-0.13Zr powder at ambient temperature that can be densified during subsequent liquid phase sintering, obtaining a functional part with zero process contaminants. Density measurement, microstructural, and mechanical investigations of the green components sintered for 5 h at different temperatures ranging from 535 °C to 610 °C indicated an improvement in properties with an increase in sintering temperature. Swelling during sintering was observed at temperatures ≥ 580 °C. Sintering at 573 °C with an extended holding time up to 60 h resulted in comparable density, compressive properties, and elastic modulus similar to that of human cortical bone. Furthermore, mercury porosimetry analysis revealed that additively manufactured Mg components could provide pores characteristics matching with those found in human bone. Keywords: 3D printing, Binder jetting, Magnesium alloys, Liquid phase sintering, Inkjet technology