An Investigation Into The Mechanical Properties Of Ti6Al4V Lattice Structures Manufactured Using Selective Laser Melting

Metal Additive Manufacturing Technology is known as the representative technology in the third Industrial Revolution. It orients to the integrated manufacturing complex structures, which the traditional manufacturing technology cannot achieve. In order to save materials and shorten the construction periods, the 3D printing products can be designed to be hollow structures and be filled with lattice materials. Based on the 3D printing products' requirements for the design of the mechanical properties, this thesis focuses on the effects of different geometric parameters on mechanical properties of Ti6A14 V lattice structures manufactured using selective laser melting.(1)present a theoretical analysis for predicting the elastic-plastic constitutive relation of body-centered tetragonal(bct) lattice structure under compressive loading, and on this basis the equations reflecting the relation among the strut aspect ratio(length/diameter), the equivalent elastic modulus and plastic yield strength of body-centered cubic(bcc) lattice structure was deduced.(2)the Ti6A14 V bcc lattice structures with different aspect ratio were manufactured by selective laser melting. The experimental stress-strain behavior and failure mechanism are obtained through quasi-static compression test. The result demonstrates that the geometrical parameter had little effect on the plasticity of the lattice structures manufactured by selective laser melting and the failure mechanism were brittle fractures.(3)the finite element software ABAQUS was adopted to calculate and analyze the compressive property of the Ti6A14 V bcc lattice structures with different aspect ratio. The stress-strain behavior and micro mechanical response of lattice structures are obtained. The results showed that the joints have the phenomena of stress focus and plastic deformation, the internal stress distribution is symmetrical and the yield behavior of strut is beam deflection.The comparison of theoretical and experimental results revealed the strut aspect ratio on the influence of the elastic modulus and strength of the lattice structure. It can provide data storage and scientific basis for the optimization design method of variable density light lattice structure which is matched with the stress condition.