Influence of structure-determining parameters on the mechanical properties and damage behavior of electron beam melted lattice structures under quasi-static and fatigue compression loading

摘要

The topology-property relationship of porous structures, especially tested under quasi-static and cyclic loadings, is an essential factor for the design and safe application of porous structures in the medical context. Within the scope of this paper, the mechanical properties and damage behavior of additively manufactured porous structures were investigated in quasi-static and fatigue compression tests taking different designs of porous structures with cubic unit cells into account. The influence of structure determining parameters on the quasi-static and fatigue properties were highlighted. For example, the mechanical properties were analytically described as a function of the porosity and the strut thickness. A global layer-by-layer damage behavior was observed both under quasi-static and fatigue lading. Moreover, a ductile local damage behavior was identified using the digital image correlation technique and the micro computed tomography. Under fatigue compression loading cubic porous structures mostly fail in the high cycle fatigue regime at stress levels above their compressive offset stresses, which is relevant for a damage-tolerant design. (c) 2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).