Influence of Processing Parameters on the Properties of Polyoxymethylene Parts Prepared by Fused Layer Modelling

Abstract

Polyoxymethylene (POM) is a promising material for fused layer modelling (FLM), but its wider use is limited by its poor adhesion to the print bed and pronounced shrinkage. Introduction of paper tape as a substrate material is proposed to increase print bed adhesion. Isothermal digital scanning calorimetry (DSC) analysis shows that higher holding temperatures delay crystallization, thereby reducing shrinkage during processing. The crystallization kinetics is observed by measuring the peak crystallization time, which increases from 3.6 s at 135 °C holding temperature to 15.6 s at 145 °C holding temperature. The principal processing parameters, such as print bed temperature and nozzle diameter, were systematically varied to assess their influence on both mechanical and tribological performance of the POM specimens. A nozzle diameter of 0.4 mm achieved a tensile strength of 43 MPa, compared with 56 MPa for injection-moulded POM. Conversely, a large nozzle diameter of 0.8 mm enhances wear resistance by six-fold compared to a smaller nozzle diameter of 0.4 mm. An optimum print bed temperature of 140 °C enhanced both mechanical and tribological performance. These findings offer a comprehensive framework for optimizing FLM process parameters to enable functional use of POM based components in engineering applications.