Ti-6Al-4V Node-enhanced Lattice Structure Prepared by Selective Laser Melting and Its Mechanical Behavior

Taking Ti-6Al-4V titanium alloy powder as the raw material, conventional and node-enhanced body-centered tetragonal lattice structures were prepared by using selective laser melting.The morphology, microstructure and compression properties of the two lattice structures were studied.And the influence of conventional heat treatment on the microstructure and mechanical properties of the node-enhanced lattice structure was explored.The results show that after increasing the laser power at the nodes, the diameter at the nodes increases and the surface roughness and porosity of the material both increase, the relative density increases by 24.8% and the prior β grains at the nodes become equiaxed.The failure mode of enhanced lattice structure changes from the 60° instantaneous collapse mode throughout the whole structure to the layer-by-layer sedimentation collapse mode, the specific elastic modulus increases by 112%, the specific compressive strength increases by 52%, and the specific energy absorption at 30% strain increases by 88%, the whole mechanical properties are improved dramatically.After heat treatment, the compressive strength of the node-enhanced lattice structure decreases, but its energy absorption capacity is improved.