Mehanička svojstva kompozita ojačanih različitim brojem slojeva lanenih vlakana i njihova primjena u brodogradnji

undergraduate thesis

• Title (english): Mechanical properties of polymer composites reinforced with different number of layers of flax fibers and their application in shipbuilding
• Author: Karla Pintur
• Mentor: Tatjana Haramina (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2022-03-02, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering

Abstract

Male brodice uobičajeno se izrađuju od polimernih kompozita ojačanih nerazgradivim staklenim vlaknima. Lanena vlakna usporedivih su mehaničkih svojstava, a uz biorazgradivost njihova je prednost i što se dobivaju iz obnovljivih izvora.
U ovom radu izrađeni su kompoziti na bazi epoksidne smole ojačane različitim brojem slojeva biaksijalno orijentiranih lanenih vlakana i istražen je utjecaj broja slojeva na rastezna svojstva kompozita. Analizirana su i savojna svojstva te međuslojna smična čvrstoća. Dobiveni podaci uspoređeni su sa zahtjevima Hrvatskog registra brodova (HRB) za polimerne kompozite ojačane staklenim vlaknima.
Istraživanje je pokazalo kako rastezna svojstva i savojni modul neovisno o broju slojeva zadovoljavaju zahtjeve HRB-a. Savojna čvrstoća i prividna međuslojna smična čvrstoća su tek malo niže od propisanih. Kompoziti s više od sedam slojeva vlakana imaju viši maseni udio vlakana i višu istezljivost, a kritična svojstva pri savojnom opterećenju su im slabija nego kod tanjih. Povećanjem udjela smole postigla bi se bolja impregnacija vlakana i uravnoteženost svojstava koja bi zadovoljila zahtjeve HRB-a.

Abstract (english)

Small boats are usually made of polymer composites reinforced with non-degradable glass fibers. Flax fibers have comparable mechanical properties, and in addition to biodegradability, their advantage is that they are obtained from renewable sources.
In this paper, composites based on epoxy resin reinforced with different number of layers of biaxially oriented flax fibers were made and the influence of the number of layers on the tensile properties of composites was investigated. Bending properties and interlayer shear strength were also analyzed. The obtained data were compared with the requirements of the Croatian Register of Shipping (CRS) for glass fiber reinforced polymer composites.
The research showed that the tensile properties and the bending module, regardless of the number of layers, meet the requirements of CRS. Flexural strength and apparent interlayer shear strength are only slightly lower than prescribed. Composites with more than seven layers of fibers have a higher mass fraction of fibers and higher elongation, and their critical bending properties are weaker than those of thinner ones. Increasing the resin content would achieve better fiber impregnation and a balance of properties that would meet the requirements of CRS.

• Keywords: biokompozit; lanena vlakna; kompozit s polimernom matricom; epoksidna smola; rastezna svojstva; savojna svojstva; prividna smična međuslojna čvrstoća
• Keywords (english): biocomposite; flax fiber; polymer matrix composite; epoxy resin; tensile properties; flexural properties; apparent shear interlayer strength
• Language: croatian
• URN:NBN: urn:nbn:hr:235:801235
• Study programme: Title: Mechanical Engineering; specializations in: Design, Process and Energy Engineering, Production Engineering, Engineering Modelling and Computer Simulation, Marine Engineering, Industrial Engineering and Management, Materials Engineering; Course: Materials Engineering; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka strojarstva (sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka strojarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2022-02-23 12:25:31