A multi-scale analytical methodology for the prediction of mechanical properties of 3D-printed materials with continuous fibres

A multi-scale analytical methodology is presented for the prediction of the mechanical properties of 3D-printed materials with continuous fibres constructed with the fused filament fabrication (FFF) technique. Initially, in micro-scale, the properties of the individual printed filaments are evaluated using different micro-models. Next, in meso-scale, the effect of voids is taken into account. Apart from the already existent models, a new concentric cylinder approach is presented for the evaluation of the effect of voids for when a transversely isotropic matrix is considered. Finally, the macro-scale properties are approximated by combining plies with different orientations using classical laminate theory (CLT). The methodology is then validated with previously and newly extracted data from numerous experiments.