Kompoziti ojačani staklenim i lanenim vlaknima pri savojnom opterećenju

undergraduate thesis

• Title (english): Composites reinforced with glass and flax fibers under flexural loading
• Author: Dominik Podgorski
• Mentor: Tatjana Haramina (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2022-09-28, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering

Abstract

U ovom završnom radu napravljena su četiri različita polimerna kompozita za izradu kojih su korištena poliesterska i epoksidna smola te staklena i lanena vlakna. Kompoziti su bili izrađeni postupkom vakuumske infuzije te su na njima provedena ispitivanja savojnih i međuslojnih svojstava u skladu s normama HRN EN ISO 14125 : 1998 i HRN EN ISO 14130 : 1997. Ispitivanjima su određene vrijednosti prividne međuslojne smične čvrstoće, savojnog modula elastičnosti, savojne čvrstoće, deformacije prilikom loma te masenog udjela vlakana. Dobiveni rezultati uspoređeni su sa zahtjevima Hrvatskog registra brodova (HRB) za kompozite ojačane staklenim vlaknima koji se uobičajeno koriste u maloj brodogradnji. Rezultati su pokazali kako je kompozit poliesterska smola / staklena vlakna postigao najbolje rezultate i zadovoljio sva svojstva, dok su ostali ispitani kompoziti zadovoljili samo jedno mehaničko svojstvo i to je bio savojni modul elastičnosti. Preostala svojstva biokompoziti nisu zadovoljili, a najbliže propisanim podacima bili su kompozit epoksidna smola / lanena vlakna i hibridni kompozit poliesterska smola / lanena i staklena vlakna, dok je kompozit poliesterska smola / lanena vlakna postigao najlošije rezultate. Analizom je zaključeno kako kompoziti ojačani biorazgradivim vlaknima imaju potencijal postati kvalitetna zamjena kompozitima sa staklenim vlaknima, ali su potrebna daljnja istraživanja koja bi trebala poboljšati postupak izrade biokompozita i povezanost između matrice i ojačala.

Abstract (english)

Four different polymer composites were made out of polyester resin, epoxy resin, glass fibers and flax fibers. Composites were produced by vacuum infusion and subjected to examinations of flexural and interlaminar properties in accordance with HRN EN ISO 14125 : 1998 and HRN EN ISO 14130 : 1997 standards. Examinations have determined the values of apparent interlaminar shear strength, flexural modulus of elasticity, flexural strength, deformation at break and mass fraction of fibers. The obtained results were compared with the requirements of the Croatian Register of Shipping (CRS) for glass fibers reinforced composites which are usually used in small shipbuilding. The results showed that the polyester resin / glass fibers composite has accomplished the best results and satisfied all the properties. On the other hand, the remaining tested composites have satisfied only one mechanical property and that was the flexural modulus of elasticity, whereas the other properties were not achieved. Epoxy resin / flax fibers composite and polyester resin / flax and glass fibers hybrid composite had the results closest to the prescribed one, whilst the polyester resin / flax fibers composite has achieved the worst results. The analysis concluded that biodegradable fibers reinforced composites have the potential to become a high-quality substitute for glass fibers reinforced composites, but further research, which will improve the production of biocomposites and connection between the matrix and the reinforcement, is needed.

• Keywords: biokompozit; poliesterska smola; epoksidna smola; lanena vlakna; staklena vlakna; savojni modul elastičnosti; savojna čvrstoća; prividna međuslojna smična čvrstoća
• Keywords (english): biocomposite; polyester resin; epoxy resin; flax fibers; glass fibers; flexural modulus of elasticity; flexural strength; apparent interlaminar shear strength
• Language: croatian
• URN:NBN: urn:nbn:hr:235:498739
• 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: 2022-09-23 11:43:31