A Comprehensive Investigation on 3D Printing of Polyamide 11 and Thermoplastic Polyurethane via Multi Jet Fusion

Abstract

Multi Jet Fusion (MJF) is a recently developed polymeric powder bed fusion (PBF) additive manufacturing technique that has received considerable attention in the industrial and scientific community due to its ability to fabricate functional and complex polymeric parts efficiently. In this work, a systematic characterization of the physicochemical properties of MJF-certified polyamide 11 (PA11) and thermoplastic polyurethane (TPU) powder was conducted. The mechanical performance and print quality of the specimens printed using both powders were then evaluated. Both PA11 and TPU powders showed irregular morphology with sharp features and had broad particle size distribution, but such features did not impair their printability significantly. According to the DSC scans, the PA11 specimen exhibited two endothermic peaks, while the TPU specimen exhibited a broad endothermic peak (116–150 °C). The PA11 specimens possessed the highest tensile strength in the Z orientation, as opposed to the TPU specimens which possessed the lowest tensile strength along the same orientation. The flexural properties of the PA11 and TPU specimens displayed a similar anisotropy where the flexural strength was highest in the Z orientation and lowest in the X orientation. The porosity values of both the PA11 and the TPU specimens were observed to be the lowest in the Z orientation and highest in the X orientation, which was the opposite of the trend observed for the flexural strength of the specimens. The PA11 specimen possessed a low coefficient of friction (COF) of 0.13 and wear rate of 8.68 × 10−5 mm3/Nm as compared to the TPU specimen, which had a COF of 0.55 and wear rate of 0.012 mm3/Nm. The PA11 specimens generally had lower roughness values on their surfaces (Ra < 25 μm), while the TPU specimens had much rougher surfaces (Ra > 40 μm). This investigation aims to uncover and explain phenomena that are unique to the MJF process of PA11 and TPU while also serving as a benchmark against similar polymeric parts printed using other PBF processes.

Toughened Bio-Polyamide 11 for Impact-Resistant Intraply Basalt/Flax Hybrid Composites

“…This is confirmed by the XRD spectra reported in Figure 4, where two different peaks can be observed at 20.4 • and 22.7 • for PA11_TL and 20.2 • and 22.8 • for PA11_P40. In the literature, it is reported that the (200) plane of the triclinic α structure appears at 20 • while the (010) and ( 210) planes appear at 23.3-23.5 • [34,35]. Moreover, the (100) plane of the α' structure, which is a pseudohexagonal δ phase, appears at 21 • [36].…”

Novel High-Speed 3D Printing Method Using Selective Oil Sintering with Thermoplastic Polyurethane Powder Printing

“…The break stress is 2.9 MPa. According to the literature[ 10 , 11 ], TPU containing carbon black will change its mechanical properties, but TPU containing carbon black will have better mechanical properties than TPU without carbon black. The stress-strain curves indicated that the pure TPU could be stretched by up to 160%.…”

Innovations in applications and prospects of bioplastics and biopolymers: a review

“…The recent advancements in research and development on polyamide 11 are focused on multi-jet fusion technology, which has enabled the fabrication of functional and convoluted polymeric parts. Multi-jet fusion is a development in polymeric powder bed fusion additive production methods (Tey et al 2021 ). The polyamide 11 polymer powder is used for deposition in the multi-jet fusion fabrication process and sintering of powder occurs when exposed to infrared radiation (Lee et al 2020 ).…”