Abstract:

Fused deposition modeling (FDM) 3D printed process has the advantages of low cost and high adaptability, and however the poor mechanical performance of the 3D printed preforms limits their wide applications. In this paper, the 3D printed preforms fabricated under four loading conditions of tension, compression, bending and torsion were taken as the research objects, and the filling rate and fill cell type were taken as the analysis parameters. The impact parameters for the filling rates of the 3D printed preforms were first determined to establish a general analytical relationship between the filling rate and geometric parameter of the lattice filling unit, and then the 3D geometric models were constructed for the 3D printed preforms with different filling rates. Furthermore, the finite element simulation analysis was performed for the 3D printed preforms to clarify the influence of filling rates on the mechanical properties under different load conditions. The simulation and experimental results indicated that there was a great influence from the filling rate on the tensile stress, compressive stress and bending stress of the 3D printed preforms, and however the influence could be ignored under the torsion. In this case, the optimum filling rates could be determined for the 3D printed preforms under the certain loading conditions. On the basis of the proposed three?dimensional modeling method, the mechanical properties of the 3D printed preforms can be simulated and analyzed effectively. This study generates a positive effect on reducing the test number of products and R&D cost.

Key words: fused deposition modeling, three dimensional printing, preform, finite element, mechanical property