Termodinamična karakterizacija zlitine EN AW-7075

Janžič, Klara (author), Medved, Jože (mentor)

Kompleksna aluminijeva zlitina EN AW-7075 (Al-Zn-Mg-Cu) spada med visoko trdne zlitine, z 5,6–6,1 mas. % Zn, 2,1–2,9 mas. % Mg in 1,2–2,0 mas. % Cu. Zaradi dobrih mehanskih lastnosti kot so visoka trdnost, lomna žilavost in dobra duktilnost ter nizka gostota in odpornost proti koroziji, se zlitino EN AW-7075 uporablja v: letalski, vojaški, pomorski in avtomobilski industriji, za plezalno opremo, sestavne dele koles, opremo za kampiranje ter tudi v prehrambeni industriji za embalažo. Namen diplomskega dela je izvedba termodinamične karakterizacije zlitine EN AW-7075. S programom Thermo-Calc smo izvedli termodinamične izračune ravnotežnega in neravnotežnega stanja in na podlagi dobljenih izračunov izrisali izopletni fazni diagram ter Scheil-ov diagram. Izvedli smo tudi diferenčno vrstično kalorimetrijo (DSC) za vzorca v litem in homogeniziranem stanju s pomočjo naprave Netzsch STA 449C Jupiter. Odčitali smo karakteristične temperature in odgovarjajoče entalpije tvorbe posameznih faz.

• Language: Slovenian
• Keywords: aluminijeve zlitine, skupina 7XXX, DSC, termodinamični izračuni
• Work type: Bachelor thesis/paper
• Organization: NTF - Faculty of Natural Sciences and Engineering
• Year: 2021
• PID: 20.500.12556/RUL-127535
• COBISS.SI-ID: 67009283
• Publication date in RUL: 13.06.2021

Secondary language

• Language: English
• Title: Thermodynamic characterization of EN AW-7075 alloy

Abstract

Complex aluminum alloy EN AW-7075 (Al-Zn-Mg-Cu) is a high-strength alloy with a 5.6 - 6.1 mass. % of zinc, 2.1-2.9 mass. % of magnesium and 1.2–2.0 mass. % of copper. Due to good mechanical properties such as high strength, fracture toughness, good ductility, low density and corrosion resistance, alloy EN AW-7075 sees its use in aerospace, military, naval, automotive industries, for climbing equipment, bicycle components, camping equipment and in the food packaging industry. The purpose of this thesis is to perform a thermodynamic characterization of the alloy EN AW-7075. With the Thermo-Calc program, we performed thermodynamic calculations of the equilibrium and non-equilibrium states, and based on the obtained calculations, we drew an isopleth phase diagram and a Scheil diagram. We also conducted differential scanning calorimetry (DSC) for the samples in cast and homogenized state using a Netzsch STA 449C Jupiter device. We determined the characteristic temperatures and the corresponding enthalpies of formation of individual phases.

• Keywords: aluminum alloys, group 7XXX, DSC, thermodynamic calculations