Effect of Hexagonal Boron Nitride (h-BN) Content on the Mechanical and Tribological Properties of Fused Deposition Modeling (FDM)-Printed PETG Composites

PETG composite filaments containing 1 wt%, 3 wt%, and 5 wt% hexagonal boron nitride (h-BN) were produced. The produced filaments were transformed into test specimens using the fused deposition modeling (FDM) technique. The tensile, compression, and wear behaviors of the composite polymer test specimens produced by the FDM method were investigated. The wear characteristic was measured using a ball-on-flat tribometer under normal loads of 5, 10, and 15 N. The worn surfaces were characterized by profilometer, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). PETG/1hBN showed the lowest coefficient of friction (COF) at all tested loads and provided a 40–46% reduction compared to neat PETG. In addition, it was observed to have the wear track with the lowest depth and the smoothest surface. Furthermore, the highest compressive yield strength among the investigated compositions was reached in these specimens. For specimens containing higher h-BN contents, a proportional improvement could not be achieved, and this was interpreted as being due to the agglomeration of the filler material reducing its effectiveness in the transfer film layer. These results show that the addition of a low amount of h-BN to PETG is an effective and easily processable method for improving the wear resistance of the PETG matrix.