# Effect of Printing Direction of 3D-Printed Nylon Under Abrasive Wear Conditions

## TL;DR

This study shows that printing direction affects the wear resistance of 3D-printed nylon, with single-orientation prints performing better.

## Contribution

The study introduces insights on how printing orientation impacts wear resistance and thermal properties of 3D-printed nylon.

## Key findings

- Alternating printing directions increase wear and expose multiple layers under normal load.
- Single-orientation prints show lower material loss and better filament cohesion.
- Abrasion alters thermal properties, increasing enthalpy by up to 144%.

## Abstract

This study evaluates the effect of printing orientation on the wear resistance of 3D-printed nylon fabricated via Fused Deposition Modeling (FDM). We conducted abrasive wear resistance tests, thermal analysis, and microstructural characterization using scanning electron microscopy before and after wear testing. The results show that alternating printing directions lead to significantly higher wear. Under a normal load of 130 N, this configuration caused the exposure of up to four layers. At the same time, single-orientation prints exhibit lower material loss and better filament cohesion. DSC analysis reveals that all printed samples, regardless of wear exposure, display dual melting temperatures (Ts1 and Ts2) due to distinct crystalline phase formations. Abrasion decreases the secondary melting temperature (Ts2) and increases enthalpy by up to 144% compared to unprinted nylon, highlighting the thermal history on structural properties. These findings emphasize the critical role of printing configurations in optimizing the tribological performance of 3D-printed nylon for industrial applications.