• Beraud, Nicolas
• Ramírez, E. A.
• Museau, Matthieu
• Pourroy, Franck
• Villeneuve, François

Abstract

The manufacturing of complex organic shapes for metallic mechanical products is becoming possible due to current advances in additive manufacturing technologies. In particular, the use of Triply Periodic Minimal Surfaces (TPMS), as elements for cellular constructs, have shown potential for the design of lightweight structures, given their advantages over traditional lattices design. TPMS patterns, being mathematically-defined open surfaces with a local minimal area, zero mean curvature and three- dimensional periodicity, can be used to create materials with continuous and interconnected reinforcements due to their smooth transitions between unit-cells. In this paper, the mechanical response of constant-thickness shell-based TPMS is explored. For this purpose, Primitive and Gyroid patterns, which are common examples of TPMS, of diverse relative densities are designed following a previously established modelling methodology. Finite Element Analysis is used to test the mechanical response of these constructs under compression and shear loads in two scenarios: a single pattern unit-cell and a matrix assembly of patterns. The response of the two tested cases are compared and discussed. As a result, power law models of mechanical properties as a function of the patterns’ relative density are proposed under a framework of Equivalent Material or Metamaterial analysis. The outcomes of the study will potentially aid in the correlation of Finite Element Analysis results with design methodologies of Functionally Graded Cellular Materials with variable density, in an effort to develop structures with a simultaneous optimization of strength and weight.

Topics

• density
• impedance spectroscopy
• surface
• strength
• finite element analysis
• metamaterial
• additive manufacturing
• gyroid