Utjecaj kovanja i toplinske obrade na mikrostrukturu i tvrdoću CuAlMn legure s prisjetljivosti oblika

master's thesis

• Title (english): The influence of forging and heat treatment on microstructure and hardness of CuAlMn shape memory alloy
• Author: Daniela Dumenčić
• Mentor: Ivana Ivanić (mentor)
• Committee member: Stjepan Kožuh (predsjednik povjerenstva)
• Committee member: Ivana Ivanić (član povjerenstva)
• Committee member: Mirko Gojić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Metallurgy; Sisak
• Defense date and country: 2022-10-24, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Metallurgy

Abstract

CuAlMn legure s prisjetljivosti oblika značajne su prvenstveno zbog primjene u elektroindustriji. U diplomskom radu istraživan je utjecaj kovanja i toplinske obrade na mikrostrukturu CuAlMn legure s prisjetljivosti oblika koja je dobivena postupkom lijevanja u grafitnu kokilu te kovanjem u šipke promjera 6,5 mm i 13 mm. Nakon kovanja, dobivene šipke toplinski su obrađene pri temperaturi od 850 ˚C, u trajanju od 30 minuta, a potom hlađene u vodi sobne temperature. Mikrostrukturna karakterizacija uzoraka prije i nakon toplinske obrade provedena je svjetlosnom mikroskopijom (LM) i pretražnom elektronskom mikroskopijom (SEM). Analizom mikrostrukture kod kovanih uzoraka primijećena je dvofazna (α+β) mikrostruktura, dok je na uzorcima koji su toplinski obrađeni vidljiva martenzitna mikrostruktura. Tvrdoća uzoraka se smanjuje kod toplinski obrađenih uzoraka u odnosu na kovane uzorke.

Abstract (english)

CuAlMn shape memory alloys are significant primarily due to their application in the electrical industry. In this paper, the investigation of influence of forging and heat treatment on microstructure of CuAlMn shape memory alloy. The alloy was obtained by casting in a graphite mold, and then forged into bars with a diameter of 6.5 mm and 13 mm. After forging, the obtained bars were heat treated at 850 ˚C for 30 minutes and then cooled in room temperature water. Microstructural characterization of the samples before and after heat treatment was performed by light microscopy (LM) and scanning electronic microscopy (SEM). Analyzing the microstructure of the forged samples a two-phase (α+β) microstructure was revealed, while the heat-treated samples showed a martensitic microstructure. The hardness decreases in heattreated samples in comparison to forged samples.

• Keywords: CuAlMn; legure s prisjetljivosti oblika; mikrostruktura; kovanje; tvrdoća
• Keywords (english): CuAlMn; shape memory alloys; microstructure; forging; hardness
• Language: croatian
• URN:NBN: urn:nbn:hr:115:964824
• Study programme: Title: Graduate study program Metallurgy; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka metalurgije (magistar/magistra inženjer/inženjerka metalurgije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2022-10-12 14:20:52