Transverzalne zaostale napetosti v različnih zvarih visoko-trdnostnih raznorodnih aluminijevih zlitin

Nose, Simon (author), Trdan, Uroš (mentor), Klobčar, Damjan (comentor)

Aluminijeve zlitine se pogosto uporabljajo v zahtevnih inženirskih aplikacijah, saj jih odlikuje dobra korozijska odpornost ter mehanske in materialne lastnosti. Razvoj novih tehnologij varjenja je omogočil tudi spajanje različnih visoko-trdnostnih aluminijevih zlitin med seboj, ki so izredno težko varive s konvencionalnimi postopki varjenja. Nove tehnologije pa nam odpirajo možnosti najrazličnejših raziskav vpliva varjenja na mehanske lastnosti zvarnih spojev. V zaključni nalogi smo zato analizirali transverzalne zaostale napetosti v spojih raznorodnih visoko-trdnostnih aluminijevih zlitin 2017A-T451 in 7075-T651. Analiza je bila opravljena na šestih vzorčnih spojih, ki so bili varjeni z metodo varjenja z gnetenjem z različnimi varilnimi pogoji. Na zvarih smo v prečni smeri glede na potek varjenja izbrali merilna mesta in nato v teh točkah z metodo rentgenske difrakcije izmerili zaostale napetosti. Na podlagi rezultatov meritev smo prikazali grafe porazdelitve zaostalih napetosti. Pokazali smo, da so v poprečju višje pozitivne oz. natezne zaostale napetosti na napredni strani zvarnega spoja. Ugotovili smo tudi, da so največja odstopanja zaostalih napetosti prisotna na nazadujoči strani zvarov, pri čemer smo najvišje vrednosti tlačnih zaostalih napetosti v iznosu 76,48 ± 22,46 MPa izmerili pri vzorcu 3 (ONP: 20 vrt/cm).

• Language: Slovenian
• Keywords: aluminijeve zlitine, varjenje z gnetenjem, zvarni spoji, zaostale napetosti, metoda rentgenske difrakcije
• Work type: Final paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: FS - Faculty of Mechanical Engineering
• Place of publishing: Ljubljana
• Publisher: [S. Nose]
• Year: 2019
• Number of pages: XIV, 44 f.
• PID: 20.500.12556/RUL-110173
• UDC: 621.791:669.715:620.1(043.2)
• COBISS.SI-ID: 16941595
• Publication date in RUL: 12.09.2019

NOSE, Simon, 2019, Transverzalne zaostale napetosti v različnih zvarih visoko-trdnostnih raznorodnih aluminijevih zlitin [online]. Bachelor’s thesis. Ljubljana : S. Nose. [Accessed 26 March 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=110173

Secondary language

• Language: English
• Title: Transverze residual stresses in various weld of high-strenght dissimilar aluminium alloys

Abstract

Aluminum alloys are widely used in demanding engineering applications, as they are characterized by good corrosion resistance as well as mechanical and material properties. Development of new welding technologies enabled joining high-strength aluminium alloys, which are know to be difficult to weld by conventional fusion welding techniques. New technologies offer different researches of the impact that welding has on the mechanical properties of the weld joint and the surrounding material. In the final project paper, we therefore analyzed the transverse residual stresses in the joints of heterogeneous high-strength aluminum alloys 2017A-T451 and 7075-T651. The analysis was performed on six sample joints that were welded with different welding parameters using friction stir welding method. Further, we have selected measuring points in the transverse direction of the weld and then the residual stresses were measured at these points using the X-ray diffraction method.Based on the results of the measurements, we have plotted the residual stress distribution graphs. We have shown that they are, on the average, higher tensile residual stresses on the forward side of the weld. We have also found that bigger extremes of residual stresses are present on the retreating side of the weld in which the highest value was in sample 3 (RPF: 20 rot/cm) where the compressive residual stresses measured were -76,48± 22,46 MPa).

• Keywords: aluminium alloys, friction stir welding, material welding, residual stress, x-ray difraction