Influence of printing material moisture on part adhesion in fused filament fabrication 3D printing

ABSTRACTFused filament fabrication plays an increasingly important role in modern manufacturing. Despite this, issues like deformations caused by thermal shrinkage are still common. These process failures, called warping, can easily be avoided by ensuring sufficient adhesion of the printed part to the build surface during the manufacturing process. Nevertheless, only a few is known about the factors which have an impact on the adhesion between a part to be printed and the build surface. Although the content of moisture in the used polymer plays an important role in every established processing method, its influence on adhesion is still unknown for fused filament fabrication. This publication investigates the influence of moisture in the printing material for the examples of build surfaces made from Pertinax and borosilicate glass and printing materials such as polylactide acid, polyvinyl alcohol and polyamide. These printing materials were characterized by thermogravimetric analyses and differential scanning calorimetry. Following adhesion tests showed that the moisture content of the printing material can alter the adhesion between the printed part and the build surface up to 68%. It was also shown that there is an optimum moisture content at which maximum adhesion is reached.KEYWORDS: Additive manufacturingmaterial extrusionbuild surface adhesion AcknowledgmentsWe would like to thank the working group of Macromolecular and Paper Chemistry of Markus Biesalski and especially Sunna Möhle-Saul for access to DSC and TGA measurements and consultation regarding setup and interpretation.Disclosure statementNo potential conflict of interest was reported by the author(s).Additional informationFundingThis work was supported by the Federal Ministry for Economic Affairs and Climate Action within the Central Innovation Programme for small and medium-sized enterprises (SMEs) under Grant 16KN084521.