Utjecaj mješavine Ar–He na oblik spoja pri AC MIG zavarivanju aluminija

undergraduate thesis

• Title (english): Influence of Ar-He mixture on joint shape at AC MIG welding of aluminium
• Author: Lovro Mišak
• Mentor: Ivica Garašić (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2024-02-28, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering; Production Mechanical Engineering

Abstract

Završni rad sastoji se od dva dijela, teorijskog i eksperimentalnog. U teorijskom dijelu završnog
rada navedena su svojstva i karakteristike aluminijskih legura općenito te je detaljnije opisana
aluminijska legura 5083 (EN AW-5083 H111). Objašnjene su najčešće greške koje se
pojavljuju kod zavarivanja aluminijskih legura. Nakon toga opisan je MIG postupak zavarivanja, navedene su prednosti i nedostaci te oprema koja se koristi za navedeni postupak.
Opisane su vrste prijenosa metala kod MIG zavarivanja. Detaljnije je objašnjen AC MIG
postupak zavarivanja te su navedeni parametri koji utječu na zavarivanje. Opisana su svojstva
zaštitnih plinova argona i helija te njihov utjecaj na svojstva i izgled zavara.
U eksperimentalnom dijelu završnog rada provedeno je zavarivanje kutnog spoja između ploča
napravljenih od aluminijske legure 5083 (EN AW-5083 H111) debljine 8 mm primjenom
AC MIG postupka zavarivanja. Za zaštitnu atmosferu kod zavarivanja korišteni su čisti argon i
mješavina argon + helij. Nakon zavarivanja provedena je makroanaliza uzoraka gdje su se
uspoređivali oblik i makrostruktura uzoraka pri upotrebi različitih plinova i različitih brzina
zavarivanja. Na temelju rezultata analize zaključeno je da korištenje mješavine argon + helij
poboljšava penetraciju u osnovni materijal, smanjuje pojavu poroznosti te povećava površinu
zavara u usporedbi s korištenjem čistog argona. Pri usporedbi različitih brzina zavarivanja,
rezultati su pokazali da se porastom brzine zavarivanja smanjuje penetracija u osnovni materijal
te se smanjuje površina zavara.

Abstract (english)

The undergraduate thesis consists of two parts, theoretical and experimental. In the theoretical
part of the the thesis, the properties and characteristics of aluminium alloys in general are listed
and the aluminium alloy 5083 (EN AW-5083 H111) is described in more detail. The most
common welding defects that occur when welding aluminium alloys were explained. After that,
the MIG welding process is described. The advantages, disadvantages and the equipment used
for the said process are listed. Types of metal transfer used in MIG welding were described.
The AC MIG welding process is explained in more detail and the parameters that affect welding
are listed. The properties of shielding gases argon and helium and their influence on the
properties and appearance of the weld were described.
In the experimental, the welding of the corner joint between the plates made of aluminium alloy
5083 (EN AW-5083 H111) with a thickness of 8 mm was carried out using the AC MIG
welding process. As a shielding gas in welding process, pure argon and a mixture of argon and
helium were used. After welding, a macroanalysis of the samples was carried out, where the
shape and macrostructure of the samples were compared when different gases and different
welding speeds were used. Based on the results of the analysis, it was concluded that the use of
argon and helium mixture improves penetration into the base material, reduces the occurrence
of porosity and increases the weld surface area compared to using pure argon. When comparing
different welding speeds, the results showed that as the welding speed increases, the penetration
into the base material reduces and the weld surface area decreases.

• Keywords: AC MIG; argon; helij; aluminijske legure; brzina zavarivanja
• Keywords (english): AC MIG; argon; helium; aluminium alloys; the welding speed
• Language: croatian
• URN:NBN: urn:nbn:hr:235:972738
• Study programme: Title: Mechanical Engineering; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka strojarstva (sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka strojarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-02-27 10:27:45