Investigating the torsional characteristics of 3D printed polyvinylidene fluoride composite

Abstract

In the recent past some studies have been reported on the compressive, tensile, and flexural properties of 3D-printed polyvinylidene fluoride (PVDF) composite-based intramedullary (IM) pins for canines. However, in actual working conditions (due to trauma or accident), the IM pin may also be under torsional loading conditions. But hitherto little has been testified on the torsional behavior of PVDF composite-based IM pins. This study highlights the torsional behavior at 1 rpm (from 0 to 800° of the angle of twist/rotation) of PVDF composite (PVDF-90%; hydroxyapatite (HAp8%); chitosan (CS2%)) based IM pin fabricated by fused filament fabrication (FFF) process. The study suggests that better torsional properties were obtained for 3D printed samples prepared at nozzle temperature (NT) of 235°C, raster angle (RA) of 45°, and printing speed (PS) of 60 mm/s respectively resulting in a maximum torque of 3.44 Nm at the angle of twist of 800° (as per ASTM A938). The morphological analysis based on scanning electron microscopy (SEM) supports the results of the fractured surface (at cross section) and along the lateral axis.