Fabrication of Mg-Ti interpenetrating phase composites with ultra-large cells via PrintCasting

Here, Mg-Ti interpenetrating phase composites with ultra-large cells were fabricated using selective laser melting and casting, including simple cubic (SC)—type and body centered cubic (BCC)—type. The results indicate that there are gaps between Mg and Ti in actual Mg-Ti composites, especially in BCC-type composites where large shrinkage cavity (with a diameter of 30 mm) appeared. Due to the higher casting stress, the gaps of BCC-type composites (80 μm) are wider than those of SC-type composites (50 μm). BCC-type lattice composites are more prone to forming shrinkage cavity at the nodes due to the spatial complexity of the lattice and the uneven temperature distribution. For ideal (without defects) SC-type and BCC-type Mg-Ti composites, the compression simulation shows that the compressive strength of these two lattice-reinforced composite materials increased by 12.7% and 15.4% respectively compared to the Mg matrix without lattice addition. This work provides a research foundation for exploring the preparation process of large-scale Mg-Ti interpenetrating phase composites.