Influence of processing and orientation print effects on the mechanical and thermal behavior of 3D-Printed ULTEM® 9085 Material

Abstract

In this paper, we investigate the print orientation effects on the macrostructure, the mechanical and thermal properties, and the strain field behavior of ULTEM® 9085 using a Stratasys Fused deposition modeling (FDM) 400 Printer. The tensile strength, failure strain, Poisson’s ratio, coefficient of thermal expansion and modulus were all shown to vary significantly depending on the build orientation of identical dogbones. FDM parts ranged in strength from 46 to 85% of strengths attainable from comparable injection-molded parts. The coefficient of variation (CV) increased from 2 to 13% as the primary layer orientation deviated from the primary load direction. CAT scan and SEM were employed to relate the corresponding macrostructure to the mechanical response of the material along the parts’ 3-primary directions, using digital image correlation (DIC). The fracture surfaces of these parts further suggest that 3D FDM materials behave more like laminated composite structures than isotropic cast resins and therefore design allowables should reflect actual part build configurations.