Z100 testing machine

The morphology, microstructure, and chemical composition of the samples were studied using Mira 3 Tescan scanning electron microscope with an EDX Oxford Instruments X-max 80 energy dispersive detector for X-ray spectroscopy. X-ray phase analysis was carried out on a Bruker Advance D8 diffractometer in the range of angles from 25° to 85° with a step of 0.02° and an exposure of 1.5 s at each step. The wavelength was 1.5406 Å. The lattice parameters were measured by the Le Bail method using software TOPASS. The particle size (PS) distribution of the powders was studied using a Fritsch Analysette 22 NanoTec plus laser diffraction unit. To calculate the particle size distribution, the Fraunhofer model was used. The electrical conductivity was measured using an AKIP-2101 voltmeter, a GPD-74303S current source, and a FLUKE-289 multimeter. Mechanical compression tests of the specimens were carried out on a Zwick/Roell Z100 testing machine.

In this study, two materials, produced by Markforged, were analysed: “Nylon White” an engineering-grade nylon released in 2019 and “Onyx”, a nylon reinforced with 14 wt% [31 (link)] short carbon fibres approximately 130 $\mathsf{\mu }$ m in length [32 (link)]. Test samples were manufactured using the Markforged Mark Two 3D printer, which uses a fused filament fabrication (FFF) technique. Uniaxial tensile and compression tests were carried out at a range of strain rates using a universal Zwick Z100 Testing Machine. The resulting strain fields in the samples were captured using an LA Vision Digital Image Correlation (DIC) system.

The rib-stiffened panels were subjected to an axial compression test on a Z100 testing machine (Zwick/Roell, Ulm, Germany) with a maximum capacity of 10 kN. Holes were drilled at both ends of the test panels to enable it to be fixed in the clamps attached to the grippers of the testing machine (Figure 5). The compression test, conducted at 24 °C, consisted in compressing the panel with a gently increasing force of 25 N per second. As a result of the load, the test panel was destroyed as the compressive force increased due to its loss of stability.