PSI - Issue 61

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Salamatian Hosseini et al. / Structual Integrity Procedia 00 (2024) 000-000 Salamatian Hosseini et al. / Structual Integrity Procedia 00 (2024) 000-000

Shadi Salamatian Hosseini et al. / Procedia Structural Integrity 61 (2024) 20–25 4. Results and discussion; fracture loads Table 3 presents the fracture loads together with the critical values of J-integral ( J c ). Also shown in this table are the Coefficient Variance (CV) values which confirms that the number of repetitions in the fracture experiments was suitable. 4. Results and discussion; fracture loads Table 3 presents the fracture loads together with the critical values of J-integral ( J c ). Also shown in this table are the Coefficient Variance (CV) values which confirms that the number of repetitions in the fracture experiments was suitable. 4. Results and discussion; fracture loads Table 3 presents the fracture loads together with the critical values of J-integral ( J c ). Also shown in this table are the Coefficient Variance (CV) values which confirms that the number of repetitions in the fracture experiments was suitable. Salamatian Hosseini et al. / Structual Integrity Procedia 00 (2024) 000-000 4. Results and discussion; fracture loads Table 3 presents the fracture loads together with the critical values of J-integral ( J c ). Also shown in this table are the Coefficient Variance (CV) values which confirms that the number of repetitions in the fracture experiments was suitable. 5 Salamatian Hosseini et al. / Structual Integrity Procedia 00 (2024) 000-000 4. Results and discussion; fracture loads Table 3 presents the fracture loads together with the critical values of J-integral ( J c ). Also shown in this table are the Coefficient Variance (CV) values which confirms that the number of repetitions in the fracture experiments was suitable. 5 Salamatian Hosseini et al. / Structual Integrity Procedia 00 (2024) 000-000 4. Results and discussion; fracture loads Table 3 presents the fracture loads together with the critical values of J-integral ( J c ). Also shown in this table are the Coefficient Variance (CV) values which confirms that the number of repetitions in the fracture experiments was suitable. Table 3. Fracture loads and critical values of J-integral for FDM-PLA samples printed with different nozzle diameters. Table 3. Fracture loads and critical values of J-integral for FDM-PLA samples printed with different nozzle diameters. Table 3. Fracture loads and critical values of J-integral for FDM-PLA samples printed with different nozzle diameters. Table 3. Fracture loads and critical values of J-integral for FDM-PLA samples printed with different nozzle diameters. Table 3. Fracture loads and critical values of J-integral for FDM-PLA samples printed with different nozzle diameters. Table 3. Fracture loads and critical values of J-integral for FDM-PLA samples printed with different nozzle diameters.

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Fracture load, (N) Fracture load, (N) Fracture load, (N) Fracture load, (N) Fracture load, (N) Fracture load, (N) Rep 3 Rep 3 Rep 3 Rep 3 Rep 3 Rep 3

Nozzle diameter, (mm) Nozzle diameter, (mm) Nozzle diameter, (mm) Nozzle diameter, (mm) Nozzle diameter, (mm) Nozzle diameter, (mm)

Raster angle, (deg) Raster angle, (deg) Raster angle, (deg) Raster angle, (deg) Raster angle, (deg) Raster angle, (deg) 0/90 0/90 0/90 0/90 0/90 0/90 45/-45 45/-45 45/-45 45/-45 45/-45 45/-45 0/90 0/90 0/90 0/90 0/90 0/90 45/-45 45/-45 45/-45 45/-45 45/-45 45/-45 0/90 0/90 0/90 0/90 0/90 0/90 45/-45 45/-45 45/-45 45/-45 45/-45 45/-45 0/90 0/90 0/90 0/90 0/90 0/90 45/-45 45/-45 45/-45 45/-45 45/-45 45/-45

J c , (J/m J c , (J/m J c , (J/m J c , (J/m J c , (J/m J c , (J/m 6078 5786 5637 5904 3161 5493 4589 6078 5786 5637 5904 3161 5493 4589 6078 5786 5637 5904 3161 5493 4589 6078 5786 5637 5904 3161 5493 4589 6078 5786 5637 5904 3161 5493 4589 6078 5786 5637 5904 3161 5493 4589 10400 10400 10400 10400 10400 10400

2 ) 2 ) 2 ) 2 ) 2 ) 2 )

Rep 1 Rep 1 Rep 1 Rep 1 Rep 1 Rep 1 2706 2844 2668 3265 2038 3080 2699 4219 2706 2844 2668 3265 2038 3080 2699 4219 2706 2844 2668 3265 2038 3080 2699 4219 2706 2844 2668 3265 2038 3080 2699 4219 2706 2844 2668 3265 2038 3080 2699 4219 2706 2844 2668 3265 2038 3080 2699 4219

Rep 2 Rep 2 Rep 2 Rep 2 Rep 2 Rep 2 2560 3011 2380 2165 2110 2565 2798 3862 2560 3011 2380 2165 2110 2565 2798 3862 2560 3011 2380 2165 2110 2565 2798 3862 2560 3011 2380 2165 2110 2565 2798 3862 2560 3011 2380 2165 2110 2565 2798 3862 2560 3011 2380 2165 2110 2565 2798 3862

Average Average Average Average Average Average

STD STD STD STD STD STD 130 306 117 449 156 211 130 306 117 449 156 211 130 306 117 449 156 211 130 306 117 449 156 211 130 306 117 449 156 211 130 306 117 449 156 211 58 58 58 58 58 58 395 395 395 395 395 395

CV * CV * CV * CV * CV * CV * 0.04 0.11 0.04 0.16 0.07 0.07 0.02 0.10 0.04 0.11 0.04 0.16 0.07 0.07 0.02 0.10 0.04 0.11 0.04 0.16 0.07 0.07 0.02 0.10 0.04 0.11 0.04 0.16 0.07 0.07 0.02 0.10 0.04 0.11 0.04 0.16 0.07 0.02 0.10 0.04 0.11 0.04 0.16 0.07 0.07 0.02 0.10

2715 2716 2527 2704 2183 2839 2778 3780 2715 2716 2527 2704 2183 2839 2778 3780 2715 2716 2527 2704 2183 2839 2778 3780 2715 2716 2527 2704 2183 2839 2778 3780 2715 2716 2527 2704 2183 2839 2778 3780 2715 2716 2527 2704 2183 2839 2778 3780

2879 2294 2535 2684 2401 2873 2838 3260 2879 2294 2535 2684 2401 2873 2838 3260 2879 2294 2535 2684 2401 2873 2838 3260 2879 2294 2535 2684 2401 2873 2838 3260 2879 2294 2535 2684 2401 2873 2838 3260 2879 2294 2535 2684 2401 2873 2838 3260

0.4 0.4 0.4 0.4 0.4 0.4 0.6 0.6 0.6 0.6 0.6 0.6 0.8 0.8 0.8 0.8 0.8 0.8 1 1 1 1 1 1

*Coefficient Variance=Standard Deviation/Mean value *Coefficient Variance=Standard Deviation/Mean value *Coefficient Variance=Standard Deviation/Mean value *Coefficient Variance=Standard Deviation/Mean value *Coefficient Variance=Standard Deviation/Mean value *Coefficient Variance=Standard Deviation/Mean value Based on Table 3, the raster angle of 45/-45 o resulted in higher fracture loads and J c values compared to the 0/90 o raster orientation. This can be mainly due to the shear stresses which are generated in the case of 45/-45 o raster configuration. The shear stresses increase the amount of plastic deformation around the crack tip, and consequently enhance the fracture properties. But in the case of 0/90 o raster angle, only half of the rasters were parallel to the pre-crack and the other half were perpendicular to it, thus, only 50% of the rasters had resistance against the crack extension. It should be noted that in the FDM components, the areas between the rasters were identified as weak spots and these zones had the least strength against the failure in FDM products. According to the linear elastic fracture mechanics, the maximum and minimum values of shear stresses occur at the angles of 45 o and 0 o , relative to the initial crack line. Therefore, crack extension in the FDM samples printed with 45/-45 o raster angles was at 45 o or -45 o (see Fig. 5). Nozzle diameter of 1 mm resulted in the highest values of fracture loads because as the nozzle diameters were increased the cross-section area of the rasters were increased too, thus, more energy was needed to fracture the SCB samples. Based on Table 3, the raster angle of 45/-45 o resulted in higher fracture loads and J c values compared to the 0/90 o raster orientation. This can be mainly due to the shear stresses which are generated in the case of 45/-45 o raster configuration. The shear stresses increase the amount of plastic deformation around the crack tip, and consequently enhance the fracture properties. But in the case of 0/90 o raster angle, only half of the rasters were parallel to the pre-crack and the other half were perpendicular to it, thus, only 50% of the rasters had resistance against the crack extension. It should be noted that in the FDM components, the areas between the rasters were identified as weak spots and these zones had the least strength against the failure in FDM products. According to the linear elastic fracture mechanics, the maximum and minimum values of shear stresses occur at the angles of 45 o and 0 o , relative to the initial crack line. Therefore, crack extension in the FDM samples printed with 45/-45 o raster angles was at 45 o or -45 o (see Fig. 5). Nozzle diameter of 1 mm resulted in the highest values of fracture loads because as the nozzle diameters were increased the cross-section area of the rasters were increased too, thus, more energy was needed to fracture the SCB samples. Based on Table 3, the raster angle of 45/-45 o resulted in higher fracture loads and J c values compared to the 0/90 o raster orientation. This can be mainly due to the shear stresses which are generated in the case of 45/-45 o raster configuration. The shear stresses increase the amount of plastic deformation around the crack tip, and consequently enhance the fracture properties. But in the case of 0/90 o raster angle, only half of the rasters were parallel to the pre-crack and the other half were perpendicular to it, thus, only 50% of the rasters had resistance against the crack extension. It should be noted that in the FDM components, the areas between the rasters were identified as weak spots and these zones had the least strength against the failure in FDM products. According to the linear elastic fracture mechanics, the maximum and minimum values of shear stresses occur at the angles of 45 o and 0 o , relative to the initial crack line. Therefore, crack extension in the FDM samples printed with 45/-45 o raster angles was at 45 o or -45 o (see Fig. 5). Nozzle diameter of 1 mm resulted in the highest values of fracture loads because as the nozzle diameters were increased the cross-section area of the rasters were increased too, thus, more energy was needed to fracture the SCB samples. Based on Table 3, the raster angle of 45/-45 o resulted in higher fracture loads and J c values compared to the 0/90 o raster orientation. This can be mainly due to the shear stresses which are generated in the case of 45/-45 o raster configuration. The shear stresses increase the amount of plastic deformation around the crack tip, and consequently enhance the fracture properties. But in the case of 0/90 o raster angle, only half of the rasters were parallel to the pre-crack and the other half were perpendicular to it, thus, only 50% of the rasters had resistance against the crack extension. It should be noted that in the FDM components, the areas between the rasters were identified as weak spots and these zones had the least strength against the failure in FDM products. According to the linear elastic fracture mechanics, the maximum and minimum values of shear stresses occur at the angles of 45 o and 0 o , relative to the initial crack line. Therefore, crack extension in the FDM samples printed with 45/-45 o raster angles was at 45 o or -45 o (see Fig. 5). Nozzle diameter of 1 mm resulted in the highest values of fracture loads because as the nozzle diameters were increased the cross-section area of the rasters were increased too, thus, more energy was needed to fracture the SCB samples. Based on Table 3, the raster angle of 45/-45 o resulted in higher fracture loads and J c values compared to the 0/90 o raster orientation. This can be mainly due to the shear stresses which are generated in the case of 45/-45 o raster configuration. The shear stresses increase the amount of plastic deformation around the crack tip, and consequently enhance the fracture properties. But in the case of 0/90 o raster angle, only half of the rasters were parallel to the pre-crack and the other half were perpendicular to it, thus, only 50% of the rasters had resistance against the crack extension. It should be noted that in the FDM components, the areas between the rasters were identified as weak spots and these zones had the least strength against the failure in FDM products. According to the linear elastic fracture mechanics, the maximum and minimum values of shear stresses occur at the angles of 45 o and 0 o , relative to the initial crack line. Therefore, crack extension in the FDM samples printed with 45/-45 o raster angles was at 45 o or -45 o (see Fig. 5). Nozzle diameter of 1 mm resulted in the highest values of fracture loads because as the nozzle diameters were increased the cross-section area of the rasters were increased too, thus, more energy was needed to fracture the SCB samples. Based on Table 3, the raster angle of 45/-45 o resulted in higher fracture loads and J c values compared to the 0/90 o raster orientation. This can be mainly due to the shear stresses which are generated in the case of 45/-45 o raster configuration. The shear stresses increase the amount of plastic deformation around the crack tip, and consequently enhance the fracture properties. But in the case of 0/90 o raster angle, only half of the rasters were parallel to the pre-crack and the other half were perpendicular to it, thus, only 50% of the rasters had resistance against the crack extension. It should be noted that in the FDM components, the areas between the rasters were identified as weak spots and these zones had the least strength against the failure in FDM products. According to the linear elastic fracture mechanics, the maximum and minimum values of shear stresses occur at the angles of 45 o and 0 o , relative to the initial crack line. Therefore, crack extension in the FDM samples printed with 45/-45 o raster angles was at 45 o or -45 o (see Fig. 5). Nozzle diameter of 1 mm resulted in the highest values of fracture loads because as the nozzle diameters were increased the cross-section area of the rasters were increased too, thus, more energy was needed to fracture the SCB samples.

Fig. 5. Representative fractured SCB samples fabricated with nozzle diameters of 0.4 and 0.8 mm. Fig. 5. Representative fractured SCB samples fabricated with nozzle diameters of 0.4 and 0.8 mm. Fig. 5. Representative fractured SCB samples fabricated with nozzle diameters of 0.4 and 0.8 mm. Fig. 5. Representative fractured SCB samples fabricated with nozzle diameters of 0.4 and 0.8 mm. Fig. 5. Representative fractured SCB samples fabricated with nozzle diameters of 0.4 and 0.8 mm. Fig. 5. Representative fractured SCB samples fabricated with nozzle diameters of 0.4 and 0.8 mm. It is finally noted that to explore the fracture mechanisms in the cracked SCB specimens, some Scanning Electron Microscopy (SEM) images were captured from the fracture surfaces. Higher level of hackle patterns and larger number of ridge markings were observed for the SCB specimens printed with the 45/-45 o raster angle compared to the case of 0/90 o . This indicates higher energy is dissipated in the 45/-45 o specimen resulting in its larger fracture resistance. Some air gaps were also detected on the fracture surfaces which can be attributed to the intrinsic nature of the FDM production process. It is finally noted that to explore the fracture mechanisms in the cracked SCB specimens, some Scanning Electron Microscopy (SEM) images were captured from the fracture surfaces. Higher level of hackle patterns and larger number of ridge markings were observed for the SCB specimens printed with the 45/-45 o raster angle compared to the case of 0/90 o . This indicates higher energy is dissipated in the 45/-45 o specimen resulting in its larger fracture resistance. Some air gaps were also detected on the fracture surfaces which can be attributed to the intrinsic nature of the FDM production process. It is finally noted that to explore the fracture mechanisms in the cracked SCB specimens, some Scanning Electron Microscopy (SEM) images were captured from the fracture surfaces. Higher level of hackle patterns and larger number of ridge markings were observed for the SCB specimens printed with the 45/-45 o raster angle compared to the case of 0/90 o . This indicates higher energy is dissipated in the 45/-45 o specimen resulting in its larger fracture resistance. Some air gaps were also detected on the fracture surfaces which can be attributed to the intrinsic nature of the FDM production process. It is finally noted that to explore the fracture mechanisms in the cracked SCB specimens, some Scanning Electron Microscopy (SEM) images were captured from the fracture surfaces. Higher level of hackle patterns and larger number of ridge markings were observed for the SCB specimens printed with the 45/-45 o raster angle compared to the case of 0/90 o . This indicates higher energy is dissipated in the 45/-45 o specimen resulting in its larger fracture resistance. Some air gaps were also detected on the fracture surfaces which can be attributed to the intrinsic nature of the FDM production process. It is finally noted that to explore the fracture mechanisms in the cracked SCB specimens, some Scanning Electron Microscopy (SEM) images were captured from the fracture surfaces. Higher level of hackle patterns and larger number of ridge markings were observed for the SCB specimens printed with the 45/-45 o raster angle compared to the case of 0/90 o . This indicates higher energy is dissipated in the 45/-45 o specimen resulting in its larger fracture resistance. Some air gaps were also detected on the fracture surfaces which can be attributed to the It is finally noted that to explore the fracture mechanisms in the cracked SCB specimens, some Scanning Electron Microscopy (SEM) images were captured from the fracture surfaces. Higher level of hackle patterns and larger number of ridge markings were observed for the SCB specimens printed with the 45/-45 o raster angle compared to the case of 0/90 o . This indicates higher energy is dissipated in the 45/-45 o specimen resulting in its