Author Contributions
Conceptualization, A.P. and F.M.; methodology, all; software, F.M.; validation, all; formal analysis, A.P.; investigation, F.M., C.P.; resources, all; data curation, F.M.; writing—original draft preparation, A.P.; writing—review and editing, F.M., C.P. and L.V.; supervision, A.P.; project administration, F.M.; funding acquisition, L.V. All authors have read and agreed to the published version of the manuscript.
Figure 1.
SLJ specimen (1 and 2 are the longitudinal and transverse direction, respectively, of T1100), t = 0.1 (AF 163) or 0.2 mm (9323). Dimensions are in mm.
Figure 1.
SLJ specimen (1 and 2 are the longitudinal and transverse direction, respectively, of T1100), t = 0.1 (AF 163) or 0.2 mm (9323). Dimensions are in mm.
Figure 2.
TRAZ-BJ specimen. Dimensions are in mm.
Figure 2.
TRAZ-BJ specimen. Dimensions are in mm.
Figure 3.
DCB and ENF specimens. W = 150 (DCB) or 180 mm (ENF), t = 0.1 (AF 163) or 0.2 mm (9323). Dashed-dotted circles represent the ENF supports and load application points. Dimensions are in mm.
Figure 3.
DCB and ENF specimens. W = 150 (DCB) or 180 mm (ENF), t = 0.1 (AF 163) or 0.2 mm (9323). Dashed-dotted circles represent the ENF supports and load application points. Dimensions are in mm.
Figure 4.
Details of the FE model for the DCB joints.
Figure 4.
Details of the FE model for the DCB joints.
Figure 5.
Details of the FE model for the ENF joints.
Figure 5.
Details of the FE model for the ENF joints.
Figure 6.
Force-displacement results of SLJ_AF163 tests.
Figure 6.
Force-displacement results of SLJ_AF163 tests.
Figure 7.
Highlight of failure location in SLJ_AF163 tests.
Figure 7.
Highlight of failure location in SLJ_AF163 tests.
Figure 8.
Force-displacement results of SLJ_9323 tests.
Figure 8.
Force-displacement results of SLJ_9323 tests.
Figure 9.
Highlight of failure location in SLJ_9323 tests.
Figure 9.
Highlight of failure location in SLJ_9323 tests.
Figure 10.
Force-displacement results of TRAZ-BJ_AF163 tests.
Figure 10.
Force-displacement results of TRAZ-BJ_AF163 tests.
Figure 11.
Highlight of failure location in TRAZ-BJ_AF163 tests. The red arrow points out the failure section.
Figure 11.
Highlight of failure location in TRAZ-BJ_AF163 tests. The red arrow points out the failure section.
Figure 12.
Force-displacement results of TRAZ-BJ_9323 tests.
Figure 12.
Force-displacement results of TRAZ-BJ_9323 tests.
Figure 13.
Highlight of failure location in TRAZ-BJ_9323 tests. The red arrow points out the failure section.
Figure 13.
Highlight of failure location in TRAZ-BJ_9323 tests. The red arrow points out the failure section.
Figure 14.
Results of the test on specimen DCB_AF163_01.
Figure 14.
Results of the test on specimen DCB_AF163_01.
Figure 15.
Results of the test on specimen DCB_AF163_02.
Figure 15.
Results of the test on specimen DCB_AF163_02.
Figure 16.
Results of the test on specimen DCB_AF163_03.
Figure 16.
Results of the test on specimen DCB_AF163_03.
Figure 17.
Results of the test on specimen DCB_9323_01.
Figure 17.
Results of the test on specimen DCB_9323_01.
Figure 18.
Results of the test on specimen DCB_9323_02.
Figure 18.
Results of the test on specimen DCB_9323_02.
Figure 19.
Results of the test on specimen DCB_9323_03.
Figure 19.
Results of the test on specimen DCB_9323_03.
Figure 20.
Results of the test on specimen ENF_AF163_01.
Figure 20.
Results of the test on specimen ENF_AF163_01.
Figure 21.
Results of the test on specimen ENF_AF163_02.
Figure 21.
Results of the test on specimen ENF_AF163_02.
Figure 22.
Results of the test on specimen ENF_AF163_03.
Figure 22.
Results of the test on specimen ENF_AF163_03.
Figure 23.
Results of the test on specimen ENF_9323_01.
Figure 23.
Results of the test on specimen ENF_9323_01.
Figure 24.
Results of the test on specimen ENF_9323_02.
Figure 24.
Results of the test on specimen ENF_9323_02.
Figure 25.
Results of the test on specimen ENF_9323_03.
Figure 25.
Results of the test on specimen ENF_9323_03.
Figure 26.
Overlap shear strength from the SLJ tests.
Figure 26.
Overlap shear strength from the SLJ tests.
Figure 27.
Results of TRAZ-BJ tests. Failure was always located in the composite adherends; hence values are representative of the T1100 out-of-plane tensile strength.
Figure 27.
Results of TRAZ-BJ tests. Failure was always located in the composite adherends; hence values are representative of the T1100 out-of-plane tensile strength.
Figure 28.
Detail of crack in the composite adherend (DCB_AF163_03 test) where it is evident that it converts into delamination after a certain propagation.
Figure 28.
Detail of crack in the composite adherend (DCB_AF163_03 test) where it is evident that it converts into delamination after a certain propagation.
Figure 29.
Mode I R-curve of DCB_AF163 joints.
Figure 29.
Mode I R-curve of DCB_AF163 joints.
Figure 30.
Sequence of crack propagation and relationship with the fracture surface of the DCB_CA_9323_01 joint.
Figure 30.
Sequence of crack propagation and relationship with the fracture surface of the DCB_CA_9323_01 joint.
Figure 31.
Mode I R-curve of DCB_9323 joints.
Figure 31.
Mode I R-curve of DCB_9323 joints.
Table 1.
Properties at environmental temperature of the materials used in this work (from supplier datasheet except EC 9323, which was tested in [
18]; ILSS = InterLaminar Shear Strength).
Table 1.
Properties at environmental temperature of the materials used in this work (from supplier datasheet except EC 9323, which was tested in [
18]; ILSS = InterLaminar Shear Strength).
Material | Modulus of Elasticity (GPa) | Tensile Strength (MPa) | Yield Strength (MPa) | Lap-Shear Strength (MPa) |
---|
T1100 | 0° tensile | 89 | 1900 | - | - |
90° tensile | 87 | 1740 | - | - |
0° compressive | 76 | 800 | - | - |
90° compressive | 80 | 740 | - | - |
0° Flexural | 75 | 1060 | - | - |
0° ILSS | - | 74 | - | - |
90° ILSS | - | 73 | - | - |
Ergal | 72,000 | 545 | 475 | - |
AF 163 | 1.1 * | 48 * | - | 48 ** |
9323 | 2.3 * | - | - | 28 *** |
Table 2.
Properties determined in previous studies [
16,
17].
Table 2.
Properties determined in previous studies [
16,
17].
Material | Modulus of Elasticity (MPa) | Strength (MPa) |
---|
T1100 laminate | Out-of-plane tensile (ASTM D 7291) | 11,288 ± 285 | 47.1 ± 2.95 |
Flexural | 62,500 | - |
Out-of-plane shear | 19,000 | - |
Table 3.
Failure location and tensile strength of SLJ_AF163 tests.
Table 3.
Failure location and tensile strength of SLJ_AF163 tests.
Specimen | Failure Location | τa [MPa] |
---|
SLJ_AF163_01 | TLC | 41.45 |
SLJ_AF163_02 | TLC | 39.47 |
SLJ_AF163_03 | TLC | 39.02 |
SLJ_AF163_04 | TLC | 38.02 |
SLJ_AF163_05 | TLC | 38.31 |
Avg. (all) | | 39.30 |
STD. DEV. (all) | | 1.34 |
Table 4.
Failure location and tensile strength of SLJ_9323 tests.
Table 4.
Failure location and tensile strength of SLJ_9323 tests.
Specimen | Failure Location | τa [MPa] |
---|
SLJ_9323_01 | FT | 32.10 |
SLJ_9323_02 | FT/adhesive | 30.96 |
SLJ_9323_03 | FT | 31.80 |
SLJ_9323_04 | FT/adhesive | 31.71 |
SLJ_9323_05 | FT | 32.10 |
Avg. (all) | | 31.70 |
STD. DEV. (all) | | 0.47 |
Table 5.
Failure location and tensile strength of TRAZ-BJ_AF163 tests.
Table 5.
Failure location and tensile strength of TRAZ-BJ_AF163 tests.
Specimen | Failure Location | Smax [MPa] |
---|
Traz-BJ_AF163_01 | Composite | 34.35 |
Traz-BJ_AF163_02 | Composite | 31.27 |
Traz-BJ_AF163_03 | Composite | 43.27 |
Traz-BJ_AF163_04 | Composite | 33.64 |
Traz-BJ_AF163_05 | Composite | 33.38 |
Avg. (all) | | 35.18 |
STD. DEV. (all) | | 4.17 |
Avg. (w/out 03) | | 33.16 |
STD. DEV. (w/out 03) | | 1.15 |
Table 6.
Failure location and tensile strength of TRAZ-BJ_9323 tests.
Table 6.
Failure location and tensile strength of TRAZ-BJ_9323 tests.
Spcimen | Failure Location | Smax [MPa] |
---|
Traz-BJ_9323_01 | Composite (1st-2nd ply) | 38.97 |
Traz-BJ_9323_02 | Composite | 31.37 |
Traz-BJ_9323_03 | Composite (1st-2nd ply) | 34.11 |
Traz-BJ_9323_04 | Composite | 35.24 |
Traz-BJ_9323_05 | Composite | 32.22 |
AV. (all) | | 34.38 |
STD. DEV. (all) | | 2.98 |
AV. (1st–2nd ply) | | 36.54 |
STD. DEV. (1st–2nd ply) | | 2.43 |
AV. (Composite) | | 32.94 |
STD. DEV. (Composite) | | 1.66 |