Vpliv toplotne obdelave na mehanske lastnosti zlitine EN AW 5051A : diplomsko delo

Gašper, Mlakar (author), Fajfar, Peter (mentor), Steinacher, Matej (comentor)

Aluminijeva zlitina EN AW 5051A se uporablja za izdelavo najrazličnejših izdelkov. Pogosto se iz nje izdelujejo ferule oz. ovalne cevi. Te se uporabljajo za pritrditev vlaken ali žic, običajno s stiskanjem ali z drugim postopkom deformiranja obroča. V diplomskem delu smo se ukvarjali s palicami iz zlitine EN AW 5051A. Danes se palice iztiskajo iz nehomogeniziranih drogov in nadalje mehko žarijo, vendar ne dosegajo zahtevane trdote pod 45 HB. Cilj diplomske naloge je bil, da smo z ustreznim homogenizacijskim žarjenjem drogov in toplotno obdelavo mehkega žarjenja palic dosegli zahtevane mehanske lastnosti oz. trdoto palic za nadaljnjo predelavo. V podjetju Impol d.o.o so se polkontinuirno odlili drogovi zlitine EN AW 5051A, nakar se je del drogov homogeniziral 5 ur na temperaturi 520 ?, preostali drogovi pa so ostali nehomogenizirani. V podjetju Impol, d.o.o so se iztiskale palice premera 28,5 mm na 35 MN indirektni iztiskalnici in smo jih nato poravnali na mehanskem razteznem stroju. Po ravnanju smo palice toplotno obdelali oz. mehko žarili v temperaturnem območju 350 ? do 450 ?, medtem ko smo čas mehkega žarjenja prilagajali glede na dobljene mehanske lastnosti. Dobljene rezultate smo analizirali in primerjali, da smo ugotovili, kakšna je razlika v mehanskih lastnostih. S pomočjo meritev mehanskih lastnosti smo prišli do ugotovitev, da so najbolj optimalni pogoji, če vzamemo zlitino z manj legirnimi elementi, jo homogeniziramo, ter žarimo pri najvišji temperaturi in minimalnem času.

• Language: Slovenian
• Keywords: Aluminij, mehko žarjenje, iztiskavanje, toplotna obdelava, mehanske lastnosti
• Work type: Bachelor thesis/paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: NTF - Faculty of Natural Sciences and Engineering
• Place of publishing: Ljubljana
• Publisher: G. Mlakar
• Year: 2023
• Number of pages: 44 f.
• PID: 20.500.12556/RUL-153335
• UDC: 669
• COBISS.SI-ID: 180654339
• Publication date in RUL: 22.12.2023

GAŠPER, Mlakar, 2023, Vpliv toplotne obdelave na mehanske lastnosti zlitine EN AW 5051A : diplomsko delo [online]. Bachelor’s thesis. Ljubljana : G. Mlakar. [Accessed 19 March 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=153335

Secondary language

• Language: English
• Title: Influence of heat treatment on mechanical properties of alloy EN AW 5051A : diploma work

Abstract

Aluminium alloy EN AW 5051A is used to manufacture a wide variety of products. It is often used to make ferrules or oval tubes. These are used to attach fibres or wires, or other ring deformation processes. In the thesis, we dealt with rods made of EN AW 5051A alloy. Today, bars are extruded from non-homogenized bars and continue to be soft annealed, but do not reach the required hardness below 45 HB. The aim of the thesis was to achieve the required mechanical properties or hardness of bars for further processing. At Impol d.o.o., bars of EN AW 5051A alloy were semi-continuously casted, after which part of the bars were homogenized for 5 hours at a temperature of 520 ␃, while the rest of the bars remained non-homogenized. At Impol d.o.o., bars with a diameter of 28.5 mm were extruded on a 35 MN indirect extrusion press and then straightened on a mechanical stretching machine. After straightening, the bars were heat treated or soft annealed in the temperature range of 350 ␃ to 450 ␃, while the soft annealing time was adjusted according to the obtained mechanical properties. The obtained results were analyzed and compared to determine the difference in mechanical properties. With the help of measurements of mechanical properties, we came to the conclusion that the most optimal conditions are if we take an alloy with fewer alloying elements, homogenize it, and anneal it at the highest temperature and minimum time.

• Keywords: Aluminium, soft annealing, extrusion, heat treatment, mechanical properties