Mechanical Properties of Truss-like and Extreme Surface-like Point Structures

Abstract:

The design and mechanical properties of porous titanium alloys has become a hot research topic in the biomedical field. Two types of Gyroid minimal surface monolithic structures, i.e. homogeneous and gradient, were designed and prepared by laser selective melting (SLM). By conducting static compression and tensile experiments on them, and comparing them with traditional truss-like cellular structures, the quasi-static compression models of five different lattice structures were established. The mesh division and analysis were carried out through the co-simulation of Hypermesh and ABAQUS. Five types of porous structure failure forms and deformation mechanisms of hollow cubic, G7, bcc, homogeneous Gyroid and gradient Gyroid were analyzed through the observation of stress-strain nephogram, plastic strain nephogram and compression experiment process. The stress-strain curves obtained by simulation were compared with the experimental results. Results show that the simulation method can better predict the maximum compressive strength of different porous structures. The results of compression and tensile experiments show that the maximum tensile properties of Gyroid lattice materials are much higher than those of truss-like structures, and the compressive properties are also superior. Among them, the G-gradient structure has the best overall mechanical properties.

Key words:laser selective melting;Ti6Al4V alloy;three-period minimal surface;finite element analysis