Lasersko enovarkovno sočelno varjenje jeklenih trakov za hladno preoblikovanje

Jure Dolinšek (Author), Borut Zorc (Mentor)

Abstract

V predelovalni industriji se za hladno preoblikovanje in/ali nanašanje različnih površinskih prevlek uporabljajo jekla z nizko vsebnostjo ogljika in silicija. Zaradi nizkega ogljikovega ekvivalenta je varivost teh jekel zelo dobra, zato se uporabljajo tudi za izdelke, kjer je varjenje končna ali pa medfazna operacija, kot npr. pri izdelavi strženske žice za elektroobločno varjenje. Namen diplomskega dela je analiza treh vrst maloogljičnih jekel (DC01, DC04 in DC06) in sočelnih zvarov na teh jeklih, skladnost jeklenih trakov s standardi ter vpliv sestave trakov na mikrostrukturo in lastnosti laserskega zvara. Izvedene so bile naslednje analize: kemijska analiza, natezni preizkus, meritve trdot, metalografski preizkus ter izračun varivosti posameznega traku glede na ogljikov ekvivalent. Jekli DC01 in DC04 sta si po vseh analizah zelo podobni, saj po standardu kemijske sestave lahko celo spadata v isti razred. Jeklo DC06 se po kemijski analizi razlikuje od prvih dveh, kar povzroči tudi razlike v mikrostrukturah zvara. Lasersko izdelani zvar na jeklih DC01 in DC04 imajo martenzitno mikrostrukturo, zaradi česar je zvar trd in krhek in pred nadaljnjim procesom redukcije ga je nujno mehko žariti, da se zmanjšajo napetosti in trdote v materialu. Mikrostruktura zvara jekla DC06 pa je feritna, zaradi česar so v področju zvara trdote bistveno nižje.

Keywords

strženska žica;maloogljična jekla;mikrostrukturna analiza;trdota;varjenje;

Data

Language:	Slovenian
Year of publishing:	2019
Typology:	2.11 - Undergraduate Thesis
Organization:	UL NTF - Faculty of Natural Sciences and Engineering
Publisher:	[J. Dolinšek]
UDC:	669
COBISS:	1823327
Views:	764
Downloads:	204
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	English
Secondary title:	laser beam single layer butt welding of steel strip for cold forming
Secondary abstract:	In the manufacturing industry low-carbon and silicon-based steels are used for cold forming and/or application of various surface coatings. Due to the low carbon equivalent the weldability of these steels is very good, that is why they are also used for products where welding is a final or interphase operation, such as, for example, in the production of a cored wire for arc welding. The purpose of the diploma thesis is the analysis of three types of low-carbon steels (DC01, DC04 and DC06) and butt welds on these steels, the conformity of steel strips with standards, and the influence of the composition of the strips on the microstructure and the properties of the laser weld. The following analyzes were carried out: chemical analysis, tensile test, hardness measurements, metallographic testing and calculation of the weldability of each type according to carbon equivalent equations. The DC01 and DC04 steels are very similar in all analyzes, since they can even fall into the same class according to the chemical composition standard. After the chemical analysis, the DC06 steel differs from the first two, which also causes differences in the weld microstructures. Steels DC01 and DC04 have martensitic microstructure, which makes the weld hard and brittle and this is why soft annealing is necessary prior to the further reduction process in order to reduce the tension and hardness of the material. The DC06 welding microstructure is ferritic making it significantly lower in hardness in the welded area.
Secondary keywords:	cored wire;low-carbon steel;microstructural analysis;hardness;welding;
Type (COBISS):	High school thesis
Study programme:	0
Embargo end date (OpenAIRE):	1970-01-01
Thesis comment:	Univ. v Ljubljani, Naravoslovnotehniška fak., Odd. za materiale in metalurgijo
Pages:	XII, 40 f.
ID:	11222815