Eco-friendly material extrusion 3D printing for fabricating W-Ni-Fe lattices with improved compressive resistance

Tungsten (W) and its alloys are prevalently utilized in many special fields, such as the military and nuclear industry, owing to their exceptional attributes, including superior hardness, high density, and remarkable resistance to high temperatures. However, there are still challenges to achieve easy preparation of porous W alloys and uncover the secrets of their mechanical behavior. In this work, a porous lattice made from W₉₃Ni_4.9Fe_2.1 with uniform microstructure was designed using enhanced material extrusion (MEX) 3D printing technology, offering exceptional formability while ensuring safety and environmental friendliness. The W₉₃Ni_4.9Fe_2.1 lattice, fabricated at an extrusion temperature of 150 °C and infill percentage of 60 % exhibits the optimal geometry and homogeneous sintering shrinkage. The W₉₃Ni_4.9Fe_2.1 lattice, fabricated at an extrusion temperature of 170 °C and infill percentage of 60 % shows the best compressive properties with the ultimate compressive strength of 1442 MPa and plastic strain of 19.8 %. The study of rheological properties of designed slurry determines the viscous flow activation energy of 1.64 kJ·mol⁻¹ for the smooth extrusion of slurry, which is crucial for the formability of W₉₃Ni_4.9Fe_2.1 lattice 3D printing. The ball milling treatment significantly improves the sinterability of W₉₃Ni_4.9Fe_2.1 powder, confirming the effectiveness of mechanical alloying. This work presents a novel approach for fabricating complex structured porous W alloy with high-performance in a low-cost and environmentally friendly manner.