Kenaf-aramid fibre-reinforced polyvinyl butyral hybrid composites for military helmet
Traditionally, the helmet shell has been used to provide protection against ballistic threats to reduce head injuries and fatalities. Owing to the high cost of aramid fibres and the necessity for environmentally friendly alternatives, a portion of aramid was replaced by plain woven kenaf fibre, w...
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| Format: | Thesis |
| Language: | English |
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2017
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| Online Access: | http://psasir.upm.edu.my/id/eprint/71106/ http://psasir.upm.edu.my/id/eprint/71106/1/FK%202017%2022%20-%20IR%2896%29edited.pdf |
| _version_ | 1848856881522540544 |
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| author | Salman, Suhad Dawood |
| author_facet | Salman, Suhad Dawood |
| author_sort | Salman, Suhad Dawood |
| building | UPM Institutional Repository |
| collection | Online Access |
| description | Traditionally, the helmet shell has been used to provide protection against
ballistic threats to reduce head injuries and fatalities. Owing to the high cost of
aramid fibres and the necessity for environmentally friendly alternatives, a
portion of aramid was replaced by plain woven kenaf fibre, with different
arrangements and thicknesses, without jeopardising the stringent
requirements demanded by military helmet specifications. Furthermore, novel
helmets have been produced and tested with a specific threat level (National
Institute of Justice standards, NIJ), in order to reduce the dependency on the
ballistic resistance components. Experiments were conducted with more focus
on the estimation the NIJ level, ballistic limit (V50), maximum energy
absorption, hybrid failure mechanism and trauma depth. The NIJ results
showed that the laminated hybrids with kenaf fibres passed the 4th level (IIIA)
up to four layers, using 9 mm FMJ ammunition. While laminated hybrid shell
with six kenaf layers and above passed the 3th level (II). Hybrid with 16
aramid/3 kenaf laminated composite recorded the highest V50 among other
hybrids composite, 633.7 m/s. The arrangement of fibre layers was also found
to affect the ballistic performance of the hybrid composites significantly,
placing woven kenaf alternate with aramid fabric layers provided a lower
ballistic limit velocity than placing woven kenaf together and aramid layers
separately for the same hybrid volume and thickness. The laminated
composites were subjected to physical, tensile, flexural, drop weight impact
and quasi-static penetration tests. The laminates composed of 19 layers and
were fabricated using different number and configurations of plain woven
kenaf and aramid layers reinforced Polyvinyl Butyral (PVB) film, by the hot
press technique. The experimental results demonstrated that the overall
mechanical properties of the kenaf/aramid hybrid were dependent on the
kenaf fibre content. Hybrid with 17 aramid/2 kenaf layers exhibited the best
mechanical properties compared to other hybrid composites. Generally, the
results suggested that stacking sequence, thickness and kenaf fibre content significantly influenced the mechanical and ballistic performance. It can be
concluded from the research that it is possible to reduce the amount of aramid
fibres in conventional PASGT (Personal Armour System Ground Troops) shell
by 21% by hybridizing aramid with kenaf fibre, thus providing a lower cost
alternative that is environmentally friendly. |
| first_indexed | 2025-11-15T11:48:42Z |
| format | Thesis |
| id | upm-71106 |
| institution | Universiti Putra Malaysia |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-15T11:48:42Z |
| publishDate | 2017 |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | upm-711062025-07-10T03:53:13Z http://psasir.upm.edu.my/id/eprint/71106/ Kenaf-aramid fibre-reinforced polyvinyl butyral hybrid composites for military helmet Salman, Suhad Dawood Traditionally, the helmet shell has been used to provide protection against ballistic threats to reduce head injuries and fatalities. Owing to the high cost of aramid fibres and the necessity for environmentally friendly alternatives, a portion of aramid was replaced by plain woven kenaf fibre, with different arrangements and thicknesses, without jeopardising the stringent requirements demanded by military helmet specifications. Furthermore, novel helmets have been produced and tested with a specific threat level (National Institute of Justice standards, NIJ), in order to reduce the dependency on the ballistic resistance components. Experiments were conducted with more focus on the estimation the NIJ level, ballistic limit (V50), maximum energy absorption, hybrid failure mechanism and trauma depth. The NIJ results showed that the laminated hybrids with kenaf fibres passed the 4th level (IIIA) up to four layers, using 9 mm FMJ ammunition. While laminated hybrid shell with six kenaf layers and above passed the 3th level (II). Hybrid with 16 aramid/3 kenaf laminated composite recorded the highest V50 among other hybrids composite, 633.7 m/s. The arrangement of fibre layers was also found to affect the ballistic performance of the hybrid composites significantly, placing woven kenaf alternate with aramid fabric layers provided a lower ballistic limit velocity than placing woven kenaf together and aramid layers separately for the same hybrid volume and thickness. The laminated composites were subjected to physical, tensile, flexural, drop weight impact and quasi-static penetration tests. The laminates composed of 19 layers and were fabricated using different number and configurations of plain woven kenaf and aramid layers reinforced Polyvinyl Butyral (PVB) film, by the hot press technique. The experimental results demonstrated that the overall mechanical properties of the kenaf/aramid hybrid were dependent on the kenaf fibre content. Hybrid with 17 aramid/2 kenaf layers exhibited the best mechanical properties compared to other hybrid composites. Generally, the results suggested that stacking sequence, thickness and kenaf fibre content significantly influenced the mechanical and ballistic performance. It can be concluded from the research that it is possible to reduce the amount of aramid fibres in conventional PASGT (Personal Armour System Ground Troops) shell by 21% by hybridizing aramid with kenaf fibre, thus providing a lower cost alternative that is environmentally friendly. 2017-01 Thesis NonPeerReviewed text en http://psasir.upm.edu.my/id/eprint/71106/1/FK%202017%2022%20-%20IR%2896%29edited.pdf Salman, Suhad Dawood (2017) Kenaf-aramid fibre-reinforced polyvinyl butyral hybrid composites for military helmet. Doctoral thesis, Universiti Putra Malaysia. http://ethesis.upm.edu.my/id/eprint/12429/ Mechanical engineering Materials - Technology |
| spellingShingle | Mechanical engineering Materials - Technology Salman, Suhad Dawood Kenaf-aramid fibre-reinforced polyvinyl butyral hybrid composites for military helmet |
| title | Kenaf-aramid fibre-reinforced polyvinyl butyral hybrid composites for military helmet |
| title_full | Kenaf-aramid fibre-reinforced polyvinyl butyral hybrid composites for military helmet |
| title_fullStr | Kenaf-aramid fibre-reinforced polyvinyl butyral hybrid composites for military helmet |
| title_full_unstemmed | Kenaf-aramid fibre-reinforced polyvinyl butyral hybrid composites for military helmet |
| title_short | Kenaf-aramid fibre-reinforced polyvinyl butyral hybrid composites for military helmet |
| title_sort | kenaf-aramid fibre-reinforced polyvinyl butyral hybrid composites for military helmet |
| topic | Mechanical engineering Materials - Technology |
| url | http://psasir.upm.edu.my/id/eprint/71106/ http://psasir.upm.edu.my/id/eprint/71106/ http://psasir.upm.edu.my/id/eprint/71106/1/FK%202017%2022%20-%20IR%2896%29edited.pdf |