Layer-to-layer physical characteristics and compression behavior of 3D printed polymer metastructures fabricated using different process parameters

Abstract

The extrusion-based three-dimensional printing technology such as fused deposition modeling (FDM) is the widely used one owing to its low cost. The FDM method can be used to fabricate parts with different fill densities, fill patterns, and process parameters such as extrusion temperature and print speed. In this research, influence of process parameters such as extrusion temperature and print speed on the physical characteristics such as the shape and the size of printed fibers in each layer, the fiber distance, and the fiber-to-fiber interface are investigated. In addition, their effects on mechanical characteristics of the printed samples are examined and interpreted with respect to the layer physical characteristics. To accomplish this, metastructure specimens were fabricated using acrylonitrile butadiene styrene polymer on a MakerBot 2X Replicator 3D printer. Three different extrusion temperatures (210, 230, and 250°C) and print speeds (100, 125, and 150 mm/s) were considered with an infill density of 50%. Optical microscopy was performed for layer physical characterization while the compression tests were done to evaluate the mechanical properties such as the failure strength, yield strength, and compressive modulus. It is observed that the print speed has minimal effect on mechanical properties; however, an improvement in mechanical properties is observed at higher fabrication temperature. Also, the lower fabrication temperature results in more uniform features within the layers as compared to those printed at higher extrusion temperature.

The influence of fused filament fabrication printing parameters on the mechanical properties of a thermoplastic elastomer

“…This effect has been observed in some work with ABS (Patibandla and Mian, 2020) and PLA (Kuznetsov et al , 2020). One study in ABS reported that increasing PS from 100 to 150 mm/s slightly increased the tensile modulus but had no effect on strength properties (Patibandla and Mian, 2020). In PLA, increasing PS had a minor but positive effect on tensile strength (Kuznetsov et al , 2020).…”

“…This has been expected to hold the temperature above the glass transition temperature longer, allowing for entanglement of polymer chains and increasing stiffness and strength (Lee and Wu, 2020). This effect has been observed in some work with ABS (Patibandla and Mian, 2020) and PLA (Kuznetsov et al, 2020). One study in ABS reported that increasing PS from 100 to 150 mm/s slightly increased the tensile modulus but had no effect on strength properties (Patibandla and Mian, 2020).…”

“…Industrial FFF equipment may allow for the temperature of the build environment to be controlled, and prior research suggests this may have significant effects on layer bonding (Yan et al , 2000). Higher ETs have been found to improve the strength and modulus of printed parts by increasing the contact area between printed layers, which reduces peak stresses compared to a smaller contact area under a given load (Patibandla and Mian, 2020). Higher BTs were found to produce smaller crystals and reduce void size within PLA, increasing impact strength (Wang et al , 2017).…”

Effect of Printing Parameters on the Thermal and Mechanical Properties of 3D-Printed PLA and PETG, Using Fused Deposition Modeling

“…The stress in compression largely exceeded that measured in the tension, for any given strain. A strong tension and compression asymmetry was observed [ 32 , 33 ]. This was caused by the residual stress, which was due to the cooling down of the specimen to room temperature.…”

Design and engineering of high‐performance triboelectric nanogenerator for ubiquitous unattended devices

“…The direct mechanical wear between triboelectric materials leads to TENG devices' poor stability with unstable outputs. Studies have shown that increasing the porosity of materials and decreasing the effective Young's modulus make the triboelectric materials more deformable and increase the effective contact area, resulting in an improved TENG performance and mechanical stability, 94,119,145,146,157 through introducing 3D printed metastructure, [158][159][160] auxetic structures, [161][162][163] and so forth. For instance, Matlack et al 158 suggested that the 3D-printed meta-structure with embedded resonators could not only reduce the overall mass of the device but also expand and reduce the Bragg gap, which has a unique advantage for the absorption of low-frequency vibration energy.…”