Mechanical Properties of Additively Manufactured Thermoplastic Polyurethane (TPU) Material Affected by Various Processing Parameters
Abstract
:1. Introduction
2. Materials and Methods
2.1. Test Specimens
2.2. Processing Parameters
2.2.1. Build Orientation
2.2.2. Post-Processing
2.2.3. Powder Mix Ratio
2.3. Tensile Test Setup
2.4. Scanning Electron Microscope (SEM)
2.5. Particle-Size Distribution (PSD)
2.6. Melt Flow Rate (MFR)
2.7. Differential Scanning Calorimetry (DSC)
3. Results and Discussion
3.1. Effect of Build Orientation
3.2. Effect of Post-Processing
3.3. Effect of Powder Mix Ratio
4. Conclusions
- The most significant way to improve the mechanical properties of printed parts is to increase the mix ratio of the new powder. The new powder has better particle quality and thermal properties, which are more effective for SLS processing.
- TPU specimens printed in flat and on-edge orientations exhibit similar superior mechanical properties. For the specimens printed in upright orientation, the tensile strength is about 40% lower and the deformability is about 60% lower compared to the other two orientations.
- Post-processing can substantially enhance the deformability of the specimens. For flat, on-edge and upright orientations, the deformability can be increased by 40.1%, 73.5% and 41.0%, respectively.
Author Contributions
Funding
Conflicts of Interest
References
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Dimension | Value (mm) |
---|---|
entry 1 | data |
A. Overall length (minimum) | 115 |
B. Width of ends | 25 ± 1 |
C. Length of the narrow portion | 33 ± 2 |
D. Width of the narrow portion | 6.2 ± 0.2 |
E. Transition radius outside | 14 ± 1 |
F. Transition radius inside | 25 ± 2 |
Test length | 25 ± 0.5 |
Thickness | 2 ± 0.2 |
Parameters | Value |
---|---|
Build orientation | Flat, on-edge, upright |
Post-processing method | Chemical treatment, none |
Powder mix ratio | |
(new powder: reused powder) | 3:7; 5:5; 10:0 |
Set Number | Build Orientation | Post-Processing Method | Powder Mix Ratio (New Powder: Reused Powder) |
---|---|---|---|
1 | Flat | Chemical treatment | 3:7 |
2 | On-edge | Chemical treatment | 3:7 |
3 | Upright | Chemical treatment | 3:7 |
4 | Flat | None | 3:7 |
5 | On-edge | None | 3:7 |
6 | Upright | None | 3:7 |
7 | Flat | None | 5:5 |
8 | Flat | None | 10:0 |
Set Number | Build Orientation | ||
---|---|---|---|
1 | Flat | 6.32 | 110.46 |
2 | On-edge | 6.65 | 125.27 |
3 | Upright | 3.69 | 58.43 |
Set | Build Orientation | Post-Processing Method | ||
---|---|---|---|---|
1 | Flat | Chemical treatment | 6.32 | 110.46 |
2 | On-edge | Chemical treatment | 6.65 | 125.27 |
3 | Upright | Chemical treatment | 3.69 | 58.43 |
4 | Flat | None | 6.06 | 78.81 |
5 | On-edge | None | 4.94 | 72.20 |
6 | Upright | None | 3.63 | 41.45 |
Set Number | Mix Ratio (New Powder: Reused Powder) | ||
---|---|---|---|
4 | 3: 7 | 6.06 | 78.81 |
7 | 5: 5 | 13.81 | 233.91 |
8 | 10: 0 | 22.42 | 264.07 |
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Xu, T.; Shen, W.; Lin, X.; Xie, Y.M. Mechanical Properties of Additively Manufactured Thermoplastic Polyurethane (TPU) Material Affected by Various Processing Parameters. Polymers 2020, 12, 3010. https://doi.org/10.3390/polym12123010
Xu T, Shen W, Lin X, Xie YM. Mechanical Properties of Additively Manufactured Thermoplastic Polyurethane (TPU) Material Affected by Various Processing Parameters. Polymers. 2020; 12(12):3010. https://doi.org/10.3390/polym12123010
Chicago/Turabian StyleXu, Tao, Wei Shen, Xiaoshan Lin, and Yi Min Xie. 2020. "Mechanical Properties of Additively Manufactured Thermoplastic Polyurethane (TPU) Material Affected by Various Processing Parameters" Polymers 12, no. 12: 3010. https://doi.org/10.3390/polym12123010