A GLOBAL LEADER IN METAL AM QUALITY ASSURANCE

Transcription

1 A GLOBAL LEADER IN METAL AM QUALITY ASSURANCE Is Data From In-situ Monitoring Similar to a CT Scan? 0 0

2 Is Data From In-situ Monitoring Similar to a CT Scan? QM Meltpool objective: Quality assurance Identify areas with potential defects during and after the manufacturing process In-situ and prior to post processing Pinpoint the exact positions of potential defects within the part Eliminating guesswork Computed Tomography (CT) scan objective: Non Destructive Evaluation (NDE) Identify defects after the manufacturing process QM Meltpool data vs. Computed Tomography (CT) data Both generated from images Both comprised of voxels Different resolutions Data acquisition fundamentally different CT data is derived from material density QM meltpool data is derived from meltpool monitoring CT requires mathematical process to generate tomographic images Both need analysis software to reveal internal structure Pinpoint the exact positions of defects within the part 1

3 TECHNOLOGY: Fundamentals QM Meltpool Computed Tomography (CT) Photodiode (PHD) & Camera (CAM) Measures meltpool intensity and area Data plotted along laser toolpath Resolution (RES): 70µm Radiographs (X-ray Images); multiple projections Computer algorithm generates 3D volume Resolution: from 3µm, geometry, material, equipment dependent. Example: 140mm part, 70µm RES 2

4 TECHNOLOGY: Equipment QM Meltpool Concept Laser m2 400W Single Laser Computed Tomography (CT) Nikon XTH kV target 320kV target Reconstruction: Nikon CT Pro 3D Voxel Data Analysis and Visualization VG Studio Max 3.0 3

5 68mm 68mm TEST ARTIFACTS OS CH DC Organic Sphere (OS) Canted Helix (CH) Density Cylinders (DC) Artificial pores 30µm to 2mm Ø50mm Ø12.45mm Ø44mm 4

6 PROCESS: Inducing Defects Un-calibrated scaling Overexposure (x4) [A] A B C 68mm Cold pause (30min) [B] Restart overexposure (x1) Thick recoat layer (75µm) [C] DC core parameters DC1: Concept Laser CL20 (316L) DC2: Lower laser power 300W DC3: Smaller laser spot size 140µm DC4: Medium trace 0.075mm DC5: Large trace 0.115mm DC6: Concept Laser CL92 (17-4PH) 5

7 PROCESS: Additive Manufacturing 316L stainless steel powder Powder Size Distribution: 45µm - 15µm 6

8 DATA: Acquisition & Reconstruction 7

9 DATA: Radiographs RES: 44µm Projections: 3600 Time: 4h RES: 40µm Projections: 1040 Time: 1h RES: 37µm Projections: 3600 Time: 4h 8

10 DATA: QM PHD Intensity Images 9

11 DATA: QM CAM Meltpool Area Images 10

12 DATA: Reconstructed Voxel Volumes STL CT QM PHD QM CAM 11

13 ANALYSIS: Metrology 90% Cumulated Deviation (mm) QM PHD QM PHD CT CT QM PHD: to CT: to

14 ANALYSIS: Metrology QM PHD XY XZ YZ CT XY XZ YZ 13

15 DATA: Reconstructed Voxel Volumes STL CT QM PHD QM CAM 14 3/23/

16 ANALYSIS: Metrology QM PHD: to % Cumulated CT: to Deviation (mm) 15

17 ANALYSIS: Metrology QM PHD XY XZ YZ CT XY XZ YZ 16

18 ANALYSIS: NDE, OS STL CT QM PHD QM CAM 17

19 PHD25 PHD50 CAM25 CAM50 CT ANALYSIS: NDE, DCs DC1 DC2 DC3 DC4 DC5 DC6 PHD25 PHD50 CAM25 CAM50 CT 18

20 ANALYSIS: NDT, DCs DC1 CL20 316L DC2 Laser Power 300W DC3 Spot Size 140µm DC4 Trace 0.075mm DC5 Trace 0.115mm DC6 CL PH CT QM CAM 19

21 ANALYSIS: NDT, DCs CT QM CAM CT CAM PHD 20

22 ANALYSIS: NDE, Induced Issues, DC1 OVEREXPOSURE 30 MIN PAUSE THICK LAYER RES:40µm RES:8µm RES: 40µm RES: 8µm RES: 40µm RES: 8µm PRJ: 1040 PRJ: 3600 PRJ: 1040 PRJ: 3600 PRJ: 1040 PRJ: 3600 CT CT CT CT CT CT PHD CAM PHD CAM PHD CAM 21

23 QM CAM QM PHD ANALYSIS: QM Meltpool In-situ NORMAL OVEREXPOSURE 30 MIN PAUSE THICK LAYER 22

24 COMPARISON QM Meltpool Data Metrology (N/A) Residual stress (N/A) Downskin issues Delamination Recoater streaking Overexposure / thin powder layer Underexposure / thick powder layer In-situ detection CT Data Metrology Residual stress Downskin issues Delamination? Recoater streaking Overexposure / thin powder layer Underexposure / thick powder layer In-situ detection 23

25 CONCLUSIONS QM Meltpool detection capability Toolpath pattern issues Gross geometric overhangs Overexposure / underexposure Thin / thick powder layer Support delamination Lack of fusion QM Meltpool correlation dependent on toolpath strategy False positive Data noise Voids > 350µm (5 x RES) Reconstructed data is similar QM Meltpool should not be substituted for a CT scan Benefits of QM Meltpool R&D, R&D, R&D.. Quantitative map of energy absorption Examination of exposed layers in-situ Capability to calibrate and possibly validate computational models Potential to reduce downstream CT scans Process correlation of toolpath strategy to good material properties Very strong diagnosis tool Simultaneous in-situ data collection Quality record 24