Numerička analiza utjecaja metalografske pripreme na tvrdoću titanske legure

undergraduate thesis

• Title (english): Numerical analysis of metallographic preparation effect on the hardness of titanium alloy
• Author: Klara Šimić
• Mentor: Ljerka Slokar Benić (mentor)
• Mentor: Ivan Ivec (sumentor)
• Committee member: Stjepan Kožuh (predsjednik povjerenstva)
• Committee member: Ljerka Slokar Benić (član povjerenstva)
• Committee member: Ivan Ivec (član povjerenstva)
• Committee member: Ivana Ivanić (član povjerenstva)
• Committee member: Ivan Jandrlić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Metallurgy; Sisak
• Defense date and country: 2020-09-21, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Metallurgy

Abstract

Legure titana zbog svojih dobrih svojstava imaju sve veću primjenu u biomedicini. Međutim, u svrhu poboljšanja određenih svojstava dizajniraju se legure na bazi titana s novim kemijskim sastavima. Kako bi se one mogle karakterizirati na zadovoljavajući način, prethodno moraju biti adekvatno pripremljene. Ispravna metalografska priprema ispitnih uzoraka je pretpostavka za kvalitetno promatranje, identificiranje te evaluaciju mikrostrukturnih značajki. Stoga se parametri brušenja i poliranja moraju odabrati tako da pripremljena površina uzorka bude reprezentativna. S obzirom na to da su za već poznate standardizirane legure ti parametri dobro poznati, kod razvoja novih, ali sličnih materijala, potrebno je utvrditi odgovaraju li ti uvjeti i za pripremu novih sastava. Ukoliko to nije slučaj, potrebno je naći optimalne parametre metalografske pripreme tih sastava. U ovom radu je 12 uzoraka eksperimentalne legure uloženo u epoksidnu masu radi lakšeg rukovanja. U svrhu utvrđivanja utjecaja metalografske pripreme varirana su dva najutjecajnija parametra: vrijeme i sila brušenja, dok je brzina rotacije brusne ploče bila konstantna. Nakon brušenja najvećom gradacijom brusnog papira, uzorci su promatrani pod svjetlosnim mikroskopom kako bi se utvrdilo stanje površine. Zatim im je određena tvrdoća, kao mehaničko svojstvo koje se najčešće ispituje pri karakterizaciji materijala, metodom po Vickersu različitim opterećenjima indentora. Nakon toga, uzorci su polirani u istim uvjetima, te im je ponovno određena tvrdoća. Dobivene vrijednosti tvrdoće numerički su analizirane te su utvrđene odgovarajuće funkcionalne ovisnosti izmjerene tvrdoće o parametrima brušenja (vrijeme i sila) te o sili utiskivanja indentora.

Abstract (english)

Titanium alloys due to their good properties are increasingly used in biomedicine. However, in order to improve certain properties, titanium-based alloys with new chemical compositions are designed. In order to be characterized in a satisfactory manner, they must first be adequately prepared. Proper metallographic preparation of test specimens is a prerequisite for quality observation, identification and evaluation of microstructural features. Therefore, the grinding and polishing parameters must be selected so that the prepared sample surface is representative. Given that these parameters are well known for already known, standardized alloys, in the development of new but similar materials it is necessary to determine whether these conditions are suitable for the preparation of new compositions. If this is not the case, it is necessary to find the optimal parameters of metallographic preparation of these compositions. In this paper, 12 samples of experimental alloy were embedded in the epoxy mass for easier handling. In order to determine the influence of metallographic preparation, the two most influential parameters were varied: grinding time and force, while the speed of rotation of the grinding wheel was constant. After grinding with the highest gradation of grind paper, the samples were observed under a light microscope to determine the condition of the surface. Then their hardness was determined, as a mechanical property that is most often tested in the characterization of materials, by the Vickers method with different indenter loads. After that, the samples were polished under the same conditions, and their hardness was determined again. The obtained hardness values were numerically analyzed and the corresponding functional dependences of the measured hardness on the grinding parameters (time and force) and on the indenter indentation force were determined.

• Keywords: numerička analiza; legura titana; metalografska priprema; tvrdoća
• Keywords (english): numerical analysis; titanium alloy; metallographic preparation; hardness
• Language: croatian
• URN:NBN: urn:nbn:hr:115:171259
• Study programme: Title: Undergraduate study program Metallurgy; specializations in: Metallurgical Engineering, Industrial Ecology; Course: Metallurgical Engineering; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka metalurgije (sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka metalurgije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2020-09-24 10:07:14