Research on Space-based 3D Printing

Abstract

Space-based manufacturing technology provides a promising solution for deep space exploration and long-term space missions. The distinguished merits of 3d printing include complex geometry fabrication, minimum material waste and highly automatic operation, which have obtained interest from a number of institutes and commercial groups involving NASA, ESA, CAST and Made In Space. With the advancements on material science, increasing types of materials with varied performance are available for the 3D printing. Meanwhile, some efforts have been made to demonstrate the feasibility of using 3D printing technology in space environments. Unresolved problems are faced in application of AM (additive manufacturing) technology and needs to be researched in future study.

As the vacuum environment in space can pose a major threat to the thermal control of the conventional 3D printing process. This thesis proposes an extrusion structure for 3D printing in a vacuum environment without adequate air convection to solve the problem. Meanwhile, a thermal control strategy is proposed to minimize the potential temperature overshot in the centre tube. The temperature profile of the proposed extrusion structure and the backflowing of the molten printing material in the centre tube have been analysed, which is critical to ensure the continues printing process.

Furthermore, this thesis analyses the influences resulted from the vacuum in space environment by printing the tensile and compressive samples with FDM technology. Multiple tests have been performed to compare the difference between the samples printed in vacuum and those under atmospheric pressure. The test can provide knowledge about material characteristics and the effects on printing process in the proposed vacuum environment in space.