Direct Ink Writing of cylindrical lattice structures: A proof of concept

Printing curved lattice structures is a demanding task due to the current limitations in standard 3-axes printing technologies available in the market: a removable support structure often needs to be printed, and printing layer-by-layer to generate an inclined surface causes a significant stair-stepping effect, affecting the surface quality and leading to anisotropy in physical properties. To overcome these limitations, the connection of the printing unit to a >3-axes robotic arm seems to be a feasible solution for printing polymeric based structures, as demonstrated by previous works reported in the literature. In this paper, a method for printing by Direct Ink Writing cylindrical lattice structures is presented: three different materials, SiOC amorphous ceramic, Ti6Al4V-based composite and CaSiO3 bioceramic, are printed by the combination of extrusion of an elastomeric ink and a mandrel connected to a robotic arm. The method shows high potential for printing ceramic and metal cylindrical lattice structures and their combination.