Computer-Aided Prediction for Printable Density Limits of Additively-Manufactured Direction-Wise Stretch-Dominated Strut-Based Lattice Structures

Abstract

When topologies of the bending-dominated lattices are strengthened by introducing a strut being oriented in one cubic direction, the lattice structures may behave like a stretch-dominated one in that direction. Because of this potential, they are of interest to engineers demanding anisotropic advanced materials. But their manufacturability is as important as the mechanical advantage they can present. To manufacture these lattice structures, additive manufacturing methods like powder bed fusion are widely used. Yet, there are limits for printing these structures. In this study, taking machine precision and powder lump size relative to the unit-cell size as main factors, the printable density range was found for the first-time for the lattice structures strengthened by adding a strut in one direction. Results indicated that the printable relative density range shifted upward in comparison to lattices which were not strengthened.

Keywords

• Cellular structures
• Lattice
• Additive manufacturing
• Powder bed fusion
• Printable relative density

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