Subset radius (pixels) Median Max Min Subset radius (pixels) Median Max Min 0.60 0.40 0.20 0.00 –0.20 –0.40 –0.60 0.60 0.40 0.20 0.00 –0.20 –0.40 –0.60 0 5 10 15 20 25 30 35 40 0 5 10 15 20 25 30 35 40 0 5 10 15 20 25 30 35 40 0 5 10 15 20 25 30 35 40 2.00 1.50 1.00 0.50 0.00 –0.50 –1.00 –1.50 –2.00 0 5 10 15 20 25 30 35 40 Subset radius (pixels) Median Max Min Subset radius (pixels) Median Max Min 8.00 6.00 4.00 2.00 0.00 –2.00 –4.00 –6.00 –8.00 Subset radius (pixels) Subset radius (pixels) 0 5 10 15 20 25 30 35 40 2.00 1.50 1.00 0.50 0.00 –0.50 –1.00 –1.50 –2.00 8.00 6.00 4.00 2.00 0.00 –2.00 –4.00 –6.00 –8.00 Subset radius (pixels) 0 5 10 15 20 25 30 35 40 0 5 10 15 20 25 30 35 40 Subset radius (pixels) 40.0 30.0 20.0 10.0 0.0 –10.0 –20.0 –30.0 –40.0 40.0 30.0 20.0 10.0 0.0 –10.0 –20.0 –30.0 –40.0 Median Max Min Median Max Min Median Max Min Median Max Min Figure 4. Displacement deviation plots for baseline sample: (a) average of first five and last five images U-displacements (b) average of first five and last five images V-displacements (c) first and last image U-displacements (d) first and last image V-displacements. ME | DIGITALIMAGECORRELATION 56 M AT E R I A L S E V A L U AT I O N • N O V E M B E R 2 0 2 2 U-displacement (pixels) U-displacement ( m) V-displacement (pixels) V-displacement (pixels) V-displacement ( m) U-displacement (pixels) U-displacement ( m) V-displacement ( m)

W o WR S w Figure 5. Image and ROI selection for DIC measurements: (a) ROI selection in image (b) ROI preview. TA B L E 1 Image and ROI measurements for DIC measurements Test Sample ID Original image size after cropping (pixels) ROI size (pixel) Sample width (mm) Calibration resolution (mm/pixel) Wo Ho WR HR Sw Baseline 1752 2268 1469 1451 25.4 0.0166 50% Silicone 1470 1716 1237 1264 0.0191 50% Hyd. Oil 1398 1842 1233 1238 0.0191 50% PVA 1404 2022 1250 1223 0.0191 TA B L E 2 Comparison of U- and V- displacements for four speckle patterns at subset size of radius 40: average of the first 5 and last 5 reference images Samples ID U-displacement [pixels (µm)] V-displacement [pixels (µm)] Max Median Minimum Max Median Minimum Baseline 0.12 (2.1) 0.07 (1.2) 0.03 (0.6) –0.01 (–0.2) –0.10 (–1.6) –0.17 (–2.9) Silicone 0.22 (4.2) 0.16 (3.0) 0.11 (2.2) 0.19 (3.7) 0.15 (2.8) 0.08 (1.6) Hyd. Oil 0.43 (8.2) 0.33 (6.3) 0.27 (5.1) 0.17 (3.3) 0.12 (2.4) 0.07 (1.4) PVA 0.12 (2.3) 0.05 (1.0) –0.01 (–0.1) 0.13 (2.5) 0.09 (1.6) 0.04 (0.8) TA B L E 3 Comparison of U- and V- displacements for four speckle patterns at subset size of radius 40: average of the first and last reference images Samples ID U-displacement [pixels (µm)] V-displacement [pixels (µm)] Max Median Minimum Max Median Minnimum Baseline 0.28 (4.7) 0.16 (2.6) 0.07 (1.1) 0.01 (0.1) –0.14 (–2.3) –0.26 (–4.3) Silicone 0.41 (7.8) 0.29 (5.5) 0.18 (3.5) 0.40 (7.6) 0.28 (5.4) 0.18 (3.5) Hyd. Oil 0.63 (11.9) 0.41 (7.7) 0.31 (5.9) 0.06 (1.1) –0.06 (–1.1) –0.24 (–4.6) PVA –0.16 (–3.1) –0.28 (–5.2) –0.40 (–7.5) 0.05 (0.9) –0.11 (–2.1) –0.22 (–4.1) N O V E M B E R 2 0 2 2 • M AT E R I A L S E V A L U AT I O N 57 H o H R