Oblikovanje monolitne Al2O3 keramike lijevanjem gela

undergraduate thesis

• Title (english): Gel casting monolithic Al2O3 ceramics
• Author: Matija Juraić
• Mentor: Lidija Ćurković (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2017-03-03, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering

Abstract

U ovom radu opisan je postupak oblikovanja Al2O3 keramike tehnologijom lijevanjem gela. Primijenjeni postupak se temelji na uporabi biopolimera kitozana kao vezivnog sredstva u procesu dobivanja geliranog sustava. Tehnologija oblikovanja keramičkog praha lijevanjem gela ima mnogo prednosti nad klasičnim tipovima oblikovanja, među kojima su: mogućnost proizvodnje kompleksnih izradaka na gotovo konačne dimenzije, svestranost u smislu mogućnosti proizvodnje izradaka svih oblika i debljina presjeka, mogućnost korištenja svih keramičkih prahova i visoka ponovljivost postupka. U praktičnom dijelu rada napravljen je keramički materijal sinteriranjem osušenog sirovca dobivenog spomenutim postupkom. Primjenom kitozana maseni udio vezivnog sredstva održao se vrlo niskim, što olakšava krajnji postupak sinteriranja i ekonomski je povoljnije. Postupak se pokazao uspješnim u smislu da su dobiveni uzorci imali relativno visoku gustoću i pokazali su dobru mikrostrukturu pri analizi pretražnim elektronskim mikroskopom. Istraživanje je provedeno korištenjem dvije vrste kitozana, jedan niže, a drugi više molekularne mase, ali provedena ispitivanja nisu pokazala veću razliku među njima.

Abstract (english)

This thesis describes a production process of alumina (Al2O3) ceramics using gelcasting as a consolidation method. In this method, a biopolimer chitosan was used as a binder for the gelation process. This consolidation method has many advantages over other traditionally used methods, such as: capability of producing complex parts to near net dimensions, capability of producing parts of different shapes and cross sections, allowed use of any ceramic powder and high repeatability. The practical part of the thesis describes the process of producing a ceramic material using a dried green body made by aforementioned consolidation method. By using chitosan, low binder content was achieved which primarily eases binder burnout, but it's also more economically feasible.The process was deemed successful as the sintered parts showed relatively high density and good microstructure, which was studied by a scanning electron microscope. This investigation was conducted with two versions of chitosan, one group with low and the other group with high molecular weight, but they showed no major difference.

• Keywords: tehnička keramika; aluminijev oksid (Al2O3); kitozan; oblikovanje keramike lijevanjem gela
• Keywords (english): engineering ceramics; Alumina (Al2O3); chitosan; gelcasting.
• Language: croatian
• URN:NBN: urn:nbn:hr:235:886408
• Study programme: Title: Mechanical 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: 2019-05-22 18:42:15