Izdelava in karakterizacija modificirane sive litine z lamelnim grafitom

diplomsko delo Visokošolskega strokovnega študijskega programa I. stopnje Strojništvo - Projektno aplikativni program

Rok Kenik (Avtor), Roman Šturm (Mentor), Primož Mrvar (Komentor)

Povzetek

V okviru zaključnega dela »Izdelava in karakterizacija modificirane sive litine z lamelnim grafitom« je bilo sistematično izvedeno virtualno preizkušanje ter načrtovanje preiskovane litine s tehniko gravitacijskega litja v enkratne forme, izdelane iz bentonitne peščene mešanice. Uspešno je bila postavljena livarska tehnologija in izveden obravnavani preizkusni ulitek. Izračun livarskih procesov je obsegal: strujanje litine, ohlajevanje, strjevanje ter izračun napak zaradi krčenja, erozijo forme, ohlajevalne hitrosti in temperaturna polja v ulitku in v formi ter izračun ferita in perlita v matrici FGI ter mehanskih lastnosti. Uspešno je bilo izvedeno načrtovanje in izdelava modelne naprave, formanje, sinteza dveh litin, dolegiranje in cepljenje ter litje preizkusnega ulitka ob hkratni uporabi enostavne termične analize. Karakterizacija pridobljenih vzorcev je obsegala natančno določanje kemijske sestave ter metalografsko analizo področij, ki se strjujejo z velikimi, srednjimi in majhnimi ohlajevalnimi hitrostmi. Ugotovili smo, da se pri velikih ohlajevalnih hitrostih preiskovani litini 1 in 2 strjujeta belo. Pri srednjih ohlajevalnih hitrostih pa že melirano do sivo. Nadalje je bilo ugotovljeno, da poleg kemijske sestave litine močno vpliva na izoblikovanje grafita tudi nukleacijski potencial, ki je v zvezi z učinkovitostjo cepljenja. Dobljeni grafitni delci, glede na finost, obliko, velikost in porazdelitev, v povezavi z elementi, ki stabilizirajo perlit, pomembno vplivajo na potek evtektoidne premene.

Ključne besede

diplomske naloge;gravitacijsko litje;siva litina z lamelnim grafitom;karakterizacija;lastnosti;

Podatki

Jezik:	Slovenski jezik
Leto izida:	2025
Tipologija:	2.11 - Diplomsko delo
Organizacija:	UL FS - Fakulteta za strojništvo
Založnik:	[R. Kenik]
UDK:	621.746:669.131:004.942(043.2)
COBISS:	241136899
Št. ogledov:	95
Št. prenosov:	16
Ocena:	0 (0 glasov)
Metapodatki:

Ostali podatki

Sekundarni jezik:	Angleški jezik
Sekundarni naslov:	Manufacturing and characterization of modified lamellar graphite cast iron
Sekundarni povzetek:	As part of the final thesis "Manufacturing and characterization of modified lamellar graphite cast iron," virtual testing and design of the investigated flake cast iron were systematically performed using the gravity casting technique in disposable molds made of a bentonite-sand mixture. The casting technology was successfully done and the test casting was carried out. The calculation of the casting processes included: pouring, cooling, solidification, and the calculation of defects due to shrinkage, mold erosion, cooling rates, and temperature fields in the casting and mold, as well as the calculation of ferrite and pearlite in the FGI matrix and mechanical properties. The design and manufacture of a pattern, molding, synthesis of two FGI cast irons, alloying and inoculation, and casting of the test casting were successfully carried out with the simultaneous use of simple thermal analysis. The characterization of the obtained samples included the precise determination of the chemical composition and metallographic analysis of areas that solidify at high, medium, and low cooling rates. We found, that at high cooling rates, the tested cast irons 1 and 2 solidify white. At medium cooling rates, the solidification processes was gray. Furthermore, it was found that, in addition to the chemical composition of the cast iron, the nucleation potential, which is related to the effectiveness of nucleation, also strongly influenced on the formation of graphite. The graphite particles obtained, depending on their fineness, shape, size and distribution, in conjunction with the elements that stabilize pearlite, have a dominant influence on the course of the eutectoid transformation.
Sekundarne ključne besede:	thesis;gravity casting;lamellar graphite cast iron;caracterization;properties;
Vrsta dela (COBISS):	Diplomsko delo/naloga
Študijski program:	0
Komentar na gradivo:	Univ. v Ljubljani, Fak. za strojništvo
Strani:	XX, 58 str.
ID:	26712176