Fig. 1.
Fig. 2.
Fig. 3.
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Fig. 4.
Fig. 5.
Fig. 6.
Fig. 7.
Fig. 8.
Constant technological parameters used in the study
| Parameter | Value |
|---|---|
| Infill density, % | 100 |
| Infill pattern | Rectilinear |
| Speed, mm/s | 30 |
| Bed temperature, °C | 50 |
L27 orthogonal matrix
| No. | A | B | C | D | E |
|---|---|---|---|---|---|
| 1 | 1 | 1 | 1 | 1 | 1 |
| 2 | 1 | 1 | 2 | 2 | 2 |
| 3 | 1 | 1 | 3 | 3 | 3 |
| 4 | 1 | 2 | 1 | 2 | 2 |
| 5 | 1 | 2 | 2 | 3 | 3 |
| 6 | 1 | 2 | 3 | 1 | 1 |
| 7 | 1 | 3 | 1 | 3 | 3 |
| 8 | 1 | 3 | 2 | 1 | 1 |
| 9 | 1 | 3 | 3 | 2 | 2 |
| 10 | 2 | 1 | 1 | 2 | 3 |
| 11 | 2 | 1 | 2 | 3 | 1 |
| 12 | 2 | 1 | 3 | 1 | 2 |
| 13 | 2 | 2 | 1 | 3 | 1 |
| 14 | 2 | 2 | 2 | 1 | 2 |
| 15 | 2 | 2 | 3 | 2 | 3 |
| 16 | 2 | 3 | 1 | 1 | 2 |
| 17 | 2 | 3 | 2 | 2 | 3 |
| 18 | 2 | 3 | 3 | 3 | 1 |
| 19 | 3 | 1 | 1 | 3 | 2 |
| 20 | 3 | 1 | 2 | 1 | 3 |
| 21 | 3 | 1 | 3 | 2 | 1 |
| 22 | 3 | 2 | 1 | 1 | 3 |
| 23 | 3 | 2 | 2 | 2 | 1 |
| 24 | 3 | 2 | 3 | 3 | 2 |
| 25 | 3 | 3 | 1 | 2 | 1 |
| 26 | 3 | 3 | 2 | 3 | 2 |
| 27 | 3 | 3 | 3 | 1 | 3 |
Levels of variability of input factors
| Parameter | Level | |||
|---|---|---|---|---|
| 1 | 2 | 3 | ||
| A | Layer height, mm | 0.1 | 0.2 | 0.3 |
| B | Shell | 2 | 9 | 16 |
| C | Temperature, °C | 190 | 200 | 210 |
| D | Orientation | X | Y | Z |
| E | Overlap | 15 | 40 | 65 |
Modulus of elasticity and dynamic viscosity coefficients in PLA Active material
| Number of the experiment | E0, MPa | E2, MPa | E2, MPa | μ1, MPa · s | μ2, MPa · s |
|---|---|---|---|---|---|
| 1 | 103.3 | 1.1 | 1.0 | 12 | 215 |
| 2 | 98.3 | 1.2 | 1.2 | 14 | 260 |
| 3 | 100.7 | 1.0 | 0.9 | 11 | 188 |
| 4 | 102.9 | 1.2 | 1.2 | 13 | 261 |
| 5 | 104.2 | 1.0 | 1.0 | 12 | 266 |
| 6 | 99.9 | 1.6 | 1.5 | 18 | 328 |
| 7 | 102.5 | 1.3 | 1.7 | 19 | 476 |
| 8 | 101.5 | 1.4 | 1.3 | 16 | 301 |
| 9 | 104.7 | 1.0 | 1.0 | 12 | 266 |
| 10 | 94.3 | 1.4 | 1.4 | 17 | 340 |
| 11 | 104.8 | 1.3 | 1.2 | 14 | 236 |
| 12 | 102.6 | 1.3 | 1.1 | 14 | 201 |
| 13 | 91.7 | 2.5 | 2.3 | 27 | 458 |
| 14 | 102.0 | 1.4 | 1.2 | 15 | 222 |
| 15 | 101.4 | 1.5 | 1.3 | 17 | 264 |
| 16 | 102.4 | 1.3 | 1.1 | 14 | 207 |
| 17 | 98.3 | 1.7 | 1.6 | 20 | 341 |
| 18 | 100.2 | 1.5 | 1.4 | 18 | 332 |
| 19 | 102.9 | 1.3 | 1.2 | 15 | 275 |
| 20 | 91.3 | 2.4 | 2.1 | 25 | 434 |
| 21 | 101.0 | 1.8 | 1.6 | 20 | 317 |
| 22 | 95.7 | 2.4 | 2.8 | 34 | 703 |
| 23 | 92.5 | 2.6 | 2.5 | 35 | 586 |
| 24 | 89.5 | 2.7 | 2.7 | 35 | 608 |
| 25 | 89.8 | 2.7 | 2.4 | 29 | 510 |
| 26 | 85.7 | 2.4 | 2.5 | 30 | 565 |
| 27 | 85.7 | 2.4 | 2.5 | 30 | 565 |
Influence of input factors and their levels of variation on the parameters characterising the Maxwell-Wiechert model
| Par. | Unit | Level | A | B | C | D | E |
|---|---|---|---|---|---|---|---|
| E0 | MPa | 1 | 102.0 | 99.9 | 98.4 | 98.2 | 98.3 |
| 2 | 99.7 | 97.7 | 97.6 | 98.1 | 99.0 | ||
| 3 | 92.7 | 96.7 | 98.4 | 98.0 | 97.1 | ||
| E1 | MPa | 1 | 1.2 | 1.4 | 1.7 | 1.7 | 1.8 |
| 2 | 1.6 | 1.9 | 1.7 | 1.7 | 1.5 | ||
| 3 | 2.3 | 1.8 | 1.6 | 1.7 | 1.7 | ||
| E2 | MPa | 1 | 1.2 | 1.3 | 1.7 | 1.6 | 1.7 |
| 2 | 1.4 | 1.8 | 1.6 | 1.6 | 1.5 | ||
| 3 | 2.3 | 1.7 | 1.6 | 1.7 | 1.7 | ||
| μ1 | MPa·s | 1 | 14.1 | 15.8 | 20.2 | 19.9 | 21.0 |
| 2 | 17.4 | 23.0 | 20.0 | 19.6 | 18.0 | ||
| 3 | 28.2 | 20.9 | 19.4 | 20.2 | 20.6 | ||
| μ2 | MPa·s | 1 | 284.5 | 273.9 | 382.8 | 352.9 | 364.7 |
| 2 | 288.9 | 410.6 | 356.5 | 349.3 | 318.2 | ||
| 3 | 506.9 | 395.8 | 341.0 | 378.1 | 397.4 |
Influence of input factors and their levels of variation on the percentage decrease in stress over time
| Param. Level | 1 | 2 | 3 |
|---|---|---|---|
| A | 2.64 | 3.35 | 5.53 |
| B | 3.13 | 4.26 | 4.13 |
| C | 3.86 | 3.93 | 3.73 |
| D | 3.90 | 3.79 | 3.82 |
| E | 4.04 | 3.49 | 3.99 |
PLACTIVE properties [36]
| Mechanical properties | Value | Test method |
|---|---|---|
| Tensile Yield Strength | 60 MPa | D882 |
| Tensile Strength at Break | 53 MPa | |
| Tensile Modulus | 3.6 GPa | |
| Tensile Elongation | 6 % | |
| Flexural Strength | 83 MPa | D790 |
| Flexural Modulus | 3.8 GPa |