Figure 2.
Electron beam melted vs. wrought, Ti-6Al-4V microstructure comparison: (a) EBM, Mag: 1270× (Calculated); (b) wrought, Mag: 570× (Calculated); (c) electron micrographs of Crack A showing the extent of the Crack Tip (c) and the powder consolidation flaw (d) on the inner surface.
Figure 2.
Electron beam melted vs. wrought, Ti-6Al-4V microstructure comparison: (a) EBM, Mag: 1270× (Calculated); (b) wrought, Mag: 570× (Calculated); (c) electron micrographs of Crack A showing the extent of the Crack Tip (c) and the powder consolidation flaw (d) on the inner surface.
Figure 3.
Substantiation of design value from MPS data.
Figure 3.
Substantiation of design value from MPS data.
Figure 4.
Engineering stress–strain curves of SLM 17–4 PH SS in different conditions.
Figure 4.
Engineering stress–strain curves of SLM 17–4 PH SS in different conditions.
Figure 5.
Integrated Computational Materials Engineering (ICME) Model Generator; Material modeling; process modeling, in-service Qualification: (a) Material (mechanical, fracture, fatigue), and Part Qualification; (b) Process, and Grain Modeling.
Figure 5.
Integrated Computational Materials Engineering (ICME) Model Generator; Material modeling; process modeling, in-service Qualification: (a) Material (mechanical, fracture, fatigue), and Part Qualification; (b) Process, and Grain Modeling.
Figure 6.
Process for Reproducing Scatter from Testing.
Figure 6.
Process for Reproducing Scatter from Testing.
Figure 7.
Laser powder bed fusion (LPBF) AM SS-316L Prediction/Validation different regions (humping, balling, stable): (a) Test: LPBF 2D Process Map (P-V); (b) Predicted ICME 3D Process Map (P, V, T); (c) Thermal State: Melt and melt-superheated regions; (d) Thermal State: Cooling and Solidification Regions.
Figure 7.
Laser powder bed fusion (LPBF) AM SS-316L Prediction/Validation different regions (humping, balling, stable): (a) Test: LPBF 2D Process Map (P-V); (b) Predicted ICME 3D Process Map (P, V, T); (c) Thermal State: Melt and melt-superheated regions; (d) Thermal State: Cooling and Solidification Regions.
Figure 8.
Thermal Transport Prediction of AlSi10Mg for LPBF laser melting (Laser spot 80 mm, P = 407 W and V = 1190 mm/s): (a) Thermal history for the transient thermal state of several powder beads; (b) Transient melting states; (c) Transient void ratios.
Figure 8.
Thermal Transport Prediction of AlSi10Mg for LPBF laser melting (Laser spot 80 mm, P = 407 W and V = 1190 mm/s): (a) Thermal history for the transient thermal state of several powder beads; (b) Transient melting states; (c) Transient void ratios.
Figure 9.
Comparison of experimental and simulation results for density of AlSi10Mg specimens: (a) Power vs. Speed; (b) Specimen Density Using Cross sectional microscopy based on pixel Count.
Figure 9.
Comparison of experimental and simulation results for density of AlSi10Mg specimens: (a) Power vs. Speed; (b) Specimen Density Using Cross sectional microscopy based on pixel Count.
Figure 10.
Stress–strain curves of dog bone specimens printed with XY and XZ orientation with ellipsoidal voids (0.13 mm × 0.06 mm × 0.06 mm): predicted (red) by MCQ and test (black). (a) void ratio of 0.0, XY orientation; (b) void ratio of 0.01, XZ orientation.
Figure 10.
Stress–strain curves of dog bone specimens printed with XY and XZ orientation with ellipsoidal voids (0.13 mm × 0.06 mm × 0.06 mm): predicted (red) by MCQ and test (black). (a) void ratio of 0.0, XY orientation; (b) void ratio of 0.01, XZ orientation.
Figure 11.
Variations of Test Values of Strength of AlSi10Mg.
Figure 11.
Variations of Test Values of Strength of AlSi10Mg.
Figure 12.
AlSi10Mg A-B Allowables: (a) CDF plot of Strength; (b) Sensitivity analysis of strength.
Figure 12.
AlSi10Mg A-B Allowables: (a) CDF plot of Strength; (b) Sensitivity analysis of strength.
Figure 13.
Fracture toughness of AlSi10Mg printed in the XY, XZ and YZ print orientations.
Figure 13.
Fracture toughness of AlSi10Mg printed in the XY, XZ and YZ print orientations.
Figure 14.
3D Printed Ti-4Al-4V Tensile Tests by EBM Process: (a) Horizontal and Vertical Pint; (b) Strength Scatter at RT/HT.
Figure 14.
3D Printed Ti-4Al-4V Tensile Tests by EBM Process: (a) Horizontal and Vertical Pint; (b) Strength Scatter at RT/HT.
Figure 15.
Predicted Stress–Strain Curve TI with Defects of 3D printed direct metal laser sintered (DMLS) material.
Figure 15.
Predicted Stress–Strain Curve TI with Defects of 3D printed direct metal laser sintered (DMLS) material.
Figure 16.
AM Validation: Fracture, Fatigue Properties of Un-Notched/Notched Specimen of Ti6Al4V, DMLS at RT: (a) Toughness vs. Thickness; (b) Fatigue Crack Growth vs. Test, W/o Printing; (c) S-N Prediction/Validation R = 0.1.
Figure 16.
AM Validation: Fracture, Fatigue Properties of Un-Notched/Notched Specimen of Ti6Al4V, DMLS at RT: (a) Toughness vs. Thickness; (b) Fatigue Crack Growth vs. Test, W/o Printing; (c) S-N Prediction/Validation R = 0.1.
Figure 17.
Baseline Stress–Strain Curve for Ti6Al4V.
Figure 17.
Baseline Stress–Strain Curve for Ti6Al4V.
Figure 18.
Predicted Strength Allowable and sensitivity of Ti-64Al-4V: CDF of Ultimate, yield (A), and elongation (B); (C) Sensitivity to strength: Dominant factors (Void Content, and Orientation).
Figure 18.
Predicted Strength Allowable and sensitivity of Ti-64Al-4V: CDF of Ultimate, yield (A), and elongation (B); (C) Sensitivity to strength: Dominant factors (Void Content, and Orientation).
Figure 19.
Ti-6Al-4V SS Curve variations: zoomed in to several yield strengths UTS and Elongations: (a) SS Curve Predicted by MCQ; (b) Yield Strength Variation; (c) UTS: %Elongation Variation.
Figure 19.
Ti-6Al-4V SS Curve variations: zoomed in to several yield strengths UTS and Elongations: (a) SS Curve Predicted by MCQ; (b) Yield Strength Variation; (c) UTS: %Elongation Variation.
Table 1.
AM Part Qualification Steps and Criteria.
Table 1.
AM Part Qualification Steps and Criteria.
Qualification Category | Description |
---|
1-Micro defects | Micro voids/Density during thermal history, super melting sintering and solidification |
2-Macro defects | Macro porosity: Printing error around hole and boundary |
3-Surface roughness | Diffusional creep, Triaxial stress |
4-Intergranular cracks | Diffusional creep, Biaxial stress |
5-Scatter in material properties | Stress-strain relation (yield stress, ultimate/plastic strain) due to voids (micro/macro) and cracks |
6-Fracture control plan | Characterization of fracture properties, fatigue crack growth, stress intensity curve |
7-Warpage | Evaluation of support, Residual stress |
8-Net shape | Residual stress, Baseplate removal |
9-As-built performance | In-service loading |
10-Post heat treatment | Grain growth, lower strain; thermal analysis |
Table 2.
AM machines primary process parameters.
Table 2.
AM machines primary process parameters.
Item | Parameter | Description | Controlled or Predefined |
---|
1 | Average Power, P | Total Energy Output of Laser | Controlled |
2 | Scan Velocity, v | Velocity of laser across surface | Controlled |
3 | Scan Spacing, Ss | Distance between neighboring passes | Controlled |
4 | Scan Strategy | Pattern of laser scanning (spirals, zig-zag) | Controlled |
5 | Deposition System Parameters | Recoater velocity, pressure, type, dosing | Controlled |
6 | Layer Thickness, L | Height of single powder | Controlled |
7 | Powder bed temperature, Tp | Build temperature of powder bed | Controlled |
8 | Oxygen Level, %O2 | Likely most important environment parameter | Controlled |
9 | Gas Flow Velocity, vg | Influences convective cooling | Controlled |
10 | Ambient Temperature, Tinf | Affecting cooling, rehear and residual stress | Controlled |
Table 3.
Experimental Data-Scatter in Material Parameters of AlSi10Mg [
11].
Table 3.
Experimental Data-Scatter in Material Parameters of AlSi10Mg [
11].
Parameters | Value | Range | Build |
---|
Max Strength | 4.22 KN | 0.2 kN | |
Ultimate Displacement | 210 mm | 30 mm |
Max Strength | 3.72 kN | 0.5 kN | |
Ultimate Displacement | 145 mm | 55 mm |
Max Strength | 3.7 kN | 0.2 kN | |
Ultimate Displacement | 235 mm | 65 mm |
Table 4.
Fracture toughness of AlSi10Mg [
18].
Table 4.
Fracture toughness of AlSi10Mg [
18].
Orinetation | KIC
(MPa )
| Standard Deviation
(MPa )
| Genoa Predictions
(MPa )
| Print Orientation |
---|
XY | 59.06 | 1.43 | 59.06 | |
XZ | 51.6 | 1.79 | 51.6 | |
YZ | 40.63 | 1.25 | 40.63 | |
Table 5.
Typical RT Tensile Properties for EBM Ti-6Al-4V.
Table 5.
Typical RT Tensile Properties for EBM Ti-6Al-4V.
Ti-6Al-4V | Cast | Wrought (Annealed) | EBM-As Deposited | EBM-HIP’d |
---|
UTS, ksi (MPa) | 145 (1000) | 135 (930) | 150 (1037) | 139 (957) |
YS, ksi (MPa) | 130 (896) | 128 (895) | 137 (948) | 131 (905) |
EI, % | 8 | 12 | 15 | 17 |
RA, % | – | – | 44 | 57 |
Table 6.
Tensile Data Related to Build Orientation.
Table 6.
Tensile Data Related to Build Orientation.
MOR # | Oxygen % | Density, g/cc | S/N | UTS, ksi | YS, ksi | EI, % | RA, % |
---|
221 | 0.19 | 4.3818 | Z Coupon | 139 | 131 | 16 | 19 |
X-Y Coupon | 136 | 128 | 16 | 35 |
222 | 0.19 | 4.3837 | Z Coupon | 141 | 133 | 21 | 46 |
X-Y Coupon | 134 | 126 | 19 | 36 |
233 | 0.14 | 4.3918 | Coupon | 139 | 132 | 20 | 43 |
X-Y Coupon | 139 | 131 | 20 | 49 |
234 | 0.15 | 4.3728 | Z Coupon | 143 | 132 | 18 | 50 |
X-Y Coupon | 139 | 131 | 11 | 16 |
242 | 0.20 | 4.3674 | Z Coupon | 144 | 134 | 16 | 38 |
X-Y Coupon | 142 | 131 | 16 | 34 |
249 | 0.13 | 4.4087 | Z Coupon | 148 | 138 | 16 | 38 |
X-Y Coupon | 143 | 133 | 15 | 37 |
Requiment | Max 0.2% | None | – | Min 130 | Min 119 | Min 5 | None |
Table 7.
Input Properties for Ti6Al4V and Inclusions.
Table 8.
Random variables (cause of scatter).
Table 8.
Random variables (cause of scatter).
RV Name | Mean Value | Standard Deviation | Distribution Type | COV |
---|
Air Particle VF | 5.00 × 10–3 | 2.50 × 10–4 | Normal | 0.05 |
Length | 1.57 × 10–5 | 7.85 × 10–7 | Normal | 0.05 |
Width | 3.94 × 10–5 | 1.97 × 10–6 | Normal | 0.05 |
Height | 3.94 × 10–5 | 1.97 × 10–6 | Normal | 0.05 |
Orientation Angle | 0 | 0 | Normal | 0.05 |
Orientation Type | 3.00 | 1.50 × 10–1 | Normal | 0.05 |
Table 9.
EBM 3D Printed RT/HT Test allowables vs. MCQ Prediction.
Table 9.
EBM 3D Printed RT/HT Test allowables vs. MCQ Prediction.
RT | YS, Ksi | MCQ | %Diff | UTS, Ksi | MCQ | %Diff | EI, % | MCQ | %Diff |
---|
Mean | 141.1 | 142.1 | –0.7 | 146.1 | 146.2 | –0.1 | 13.9 | 12.6 | 9.4 |
SD | 3.96 | 3.86 | 2.4 | 2.81 | 2.68 | 4.5 | 1.22 | 1.25 | –2.6 |
COV (%) | 2.81 | 2.72 | 3.1 | 1.92 | 1.83 | 4.6 | 8.78 | 9.76 | –11.1 |
HT | YS, Ksi | MCQ | %Diff | UTS, Ksi | MCQ | %Diff | EI, % | MCQ | %Diff |
Mean | 78.1 | 75.3 | 3.5 | 96.0 | 87.7 | 8.6 | 19.1 | 18.2 | 4.9 |
SD | 2.83 | 2.79 | 1.4 | 2.46 | 2.55 | –3.8 | 0.84 | 0.91 | –7.4 |
COV (%) | 3.63 | 3.71 | –2.2 | 2.56 | 2.91 | –13.6 | 4.42 | 4.98 | –12.9 |