The Effect of Binder Loading on the Pore Size of 3D Printed PMMA

Binder jetting is known to produce porous objects by depositing the binder selectively layer by layer on a powder bed. In this study, the pore size of printed parts and the correlating mechanical properties are investigated on a commercially available PMMA powder binder system. Pore sizes are measured via capillary flow porometry and mechanical properties via tensile tests. Porometry indicates that the pore size stays at a constant level of 22 mu m at 5 to 10 wt% binder loading before decreasing to 6 mu m at loadings of 30 wt% or higher. The results were compared with the mechanical testing and related to the agglomerate strength model of Rumpf. The highlights of the article are the application of a binder jetted part as a filter and the identification of a close relationship between porosity and mechanical strength, similar to phenomena in agglomeration science.

Automated summary

Binder jetting technology is used to produce porous objects by selectively depositing binder layer by layer on a powder bed. This study investigates the relationship between pore size and mechanical properties of parts printed with a commercially available PMMA powder binder system, revealing that pore size decreases as binder loading increases. The research also highlights the potential application of binder jetted parts as filters and the close relationship between porosity and mechanical strength.