Mode II delamination resistance of composites reinforced with inclined Z-pins
Z-pin reinforcements in composite materials significantly enhance the through-thickness strength by providing strong bridging forces on the delaminated surfaces of a damaged laminate. The bridging forces have been shown to be more effective in mode I dominated delamination cracks than in mode II she...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Elsevier
2016-03-01
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| Series: | Materials & Design |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S0264127516300533 |
| _version_ | 1811267242883547136 |
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| author | Beene M'membe Sam Gannon Mehdi Yasaee Stephen R. Hallett Ivana K. Partridge |
| author_facet | Beene M'membe Sam Gannon Mehdi Yasaee Stephen R. Hallett Ivana K. Partridge |
| author_sort | Beene M'membe |
| collection | DOAJ |
| description | Z-pin reinforcements in composite materials significantly enhance the through-thickness strength by providing strong bridging forces on the delaminated surfaces of a damaged laminate. The bridging forces have been shown to be more effective in mode I dominated delamination cracks than in mode II shear dominated cracks. One solution to help improve the Mode II delamination resistance of Z-pins is to incline the pins such that the angle between the longitudinal axis of the pin and the shear force load vector is reduced. In this study, the Mode II resistance of laminated composite reinforced through the thickness with inclined Z-pins is characterised. There is a notable increase in the apparent fracture toughness of composites when Z-pins are better aligned with the shear load vector (inclined) compared to the conventional, orthogonally inserted Z-pins. Brittle, catastrophic failure however occurs when the inclined Z-pins are angled against the shear load vector. For many structures the direction of the local direction of shear load cannot always be predicted, therefore a general approach for inclined Z-pins using a ± θ configuration was also investigated. With this setup, a modest improvement in the apparent fracture toughness was obtained. Keywords: Z-pins, Inclined insertion, Fracture toughness |
| first_indexed | 2024-04-12T20:58:55Z |
| format | Article |
| id | doaj.art-337c04cf7c9e4a8a9fcc81caad1f5f39 |
| institution | Directory Open Access Journal |
| issn | 0264-1275 |
| language | English |
| last_indexed | 2024-04-12T20:58:55Z |
| publishDate | 2016-03-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Materials & Design |
| spelling | doaj.art-337c04cf7c9e4a8a9fcc81caad1f5f392022-12-22T03:16:54ZengElsevierMaterials & Design0264-12752016-03-0194565572Mode II delamination resistance of composites reinforced with inclined Z-pinsBeene M'membe0Sam Gannon1Mehdi Yasaee2Stephen R. Hallett3Ivana K. Partridge4Corresponding author.; Advanced Composites Centre for Innovation and Science, Department of Aerospace Engineering, University of Bristol, University Walk, Bristol BS8 1TR, United KingdomAdvanced Composites Centre for Innovation and Science, Department of Aerospace Engineering, University of Bristol, University Walk, Bristol BS8 1TR, United KingdomAdvanced Composites Centre for Innovation and Science, Department of Aerospace Engineering, University of Bristol, University Walk, Bristol BS8 1TR, United KingdomAdvanced Composites Centre for Innovation and Science, Department of Aerospace Engineering, University of Bristol, University Walk, Bristol BS8 1TR, United KingdomAdvanced Composites Centre for Innovation and Science, Department of Aerospace Engineering, University of Bristol, University Walk, Bristol BS8 1TR, United KingdomZ-pin reinforcements in composite materials significantly enhance the through-thickness strength by providing strong bridging forces on the delaminated surfaces of a damaged laminate. The bridging forces have been shown to be more effective in mode I dominated delamination cracks than in mode II shear dominated cracks. One solution to help improve the Mode II delamination resistance of Z-pins is to incline the pins such that the angle between the longitudinal axis of the pin and the shear force load vector is reduced. In this study, the Mode II resistance of laminated composite reinforced through the thickness with inclined Z-pins is characterised. There is a notable increase in the apparent fracture toughness of composites when Z-pins are better aligned with the shear load vector (inclined) compared to the conventional, orthogonally inserted Z-pins. Brittle, catastrophic failure however occurs when the inclined Z-pins are angled against the shear load vector. For many structures the direction of the local direction of shear load cannot always be predicted, therefore a general approach for inclined Z-pins using a ± θ configuration was also investigated. With this setup, a modest improvement in the apparent fracture toughness was obtained. Keywords: Z-pins, Inclined insertion, Fracture toughnesshttp://www.sciencedirect.com/science/article/pii/S0264127516300533 |
| spellingShingle | Beene M'membe Sam Gannon Mehdi Yasaee Stephen R. Hallett Ivana K. Partridge Mode II delamination resistance of composites reinforced with inclined Z-pins Materials & Design |
| title | Mode II delamination resistance of composites reinforced with inclined Z-pins |
| title_full | Mode II delamination resistance of composites reinforced with inclined Z-pins |
| title_fullStr | Mode II delamination resistance of composites reinforced with inclined Z-pins |
| title_full_unstemmed | Mode II delamination resistance of composites reinforced with inclined Z-pins |
| title_short | Mode II delamination resistance of composites reinforced with inclined Z-pins |
| title_sort | mode ii delamination resistance of composites reinforced with inclined z pins |
| url | http://www.sciencedirect.com/science/article/pii/S0264127516300533 |
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