Multiscale Analysis of Cellular Solids Fabricated by EBM

Access full-text files

Date

2017

Authors

Arrieta, Edel
Mireles, Jorge
Stewart, Calvin
Carrasco, Cesar
Wicker, Ryan B.

Journal Title

Journal ISSN

Volume Title

Publisher

University of Texas at Austin

Abstract

Additive Manufacturing technologies such as Electron Beam Melting are empowering individuals to develop novelty materials by introducing hierarchical levels into solids. Features from the introduced architectures and the manufacturing technology grant these metamaterials with mechanical performances not commonly seen in standard solids. Thus, the response of cellular metals can now be manipulated. In general, the reported research on lattices focuses on very specific topics such as microstructure, geometry and orientation, giving the impression of isolated knowledge. However, the response of these metamaterials is the result of a complex multiscale interaction between these and other factors ranging from the microstructure of the constitutive solid, up to the cell topology. Intended as a one-stop introductory document for a new branch of material designers, the major factors affecting the response of cellular metals are identified, classified and merged into a multiscale discussion supported with evidence from a series of experiments including ASTM standard tests of EBM Ti-6Al-4V standard and lattice specimens, accompanied by failure analysis. The testing features digital image correlation (DIC) for measuring deformations, strain fields, as well as Poisson and shear effects, becoming a critical tool for the advanced characterization of specimens, especially those with complex geometries that normally would require specific instrumentation. Among these multiple determinants; microstructure, manufacturing orientation, manufacturing process, Maxwell’s stability criterion, and other geometrical features are discussed for the comprehensive understanding of two lattice designs presented herein. Lastly, Illustrative examples of how the stress-strain curves are helpful in diagnosing design features to start reverse engineering processes, and a summary of the determinants effects are included.

Description

LCSH Subject Headings

Citation