Utjecaj zadržavanja taline nakon obrade na konačnu kvalitetu nodularnog lijeva HR GJS 400-15

undergraduate thesis

• Title (english): Effect of melt retention after treatment on the final quality of nodular cast iron HR GJS 400-15
• Author: Matija Kuzmić
• Mentor: Ivan Jandrlić (mentor)
• Mentor: Zdenka Zovko Brodarac (sumentor)
• Committee member: Natalija Dolić (predsjednik povjerenstva)
• Committee member: Zdenka Zovko Brodarac (član povjerenstva)
• Committee member: Ivan Jandrlić (član povjerenstva)
• Committee member: Zoran Glavaš (član povjerenstva)
• Committee member: Anita Begić Hadžipašić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Metallurgy; Sisak
• Defense date and country: 2024-07-10, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Metallurgy

Abstract

Nodularni lijev HRN-EN-GJS-400-15 koristi se u automobilskoj industriji za izradu dijelova poput zupčanika, diferencijala i osovina zbog svoje visoke čvrstoće i dobre žilavosti.
Konstantnim rastom potražnje kupci postavljaju sve veće zahtjeve za kvalitetnijim proizvodima. Da bi proizvođači to ispunili, važno je konstantno kontrolirati kemijski sastav, minimalizirati eventualne greške u mikrostrukturi i modificirati postupke proizvodnje. U ovom završnom radu prati se proizvodnja odljevaka iz HRN-EN-GJS-400-15, točnije utjecaj vremena zadržavanja taline nakon obrade u loncu na konačnu kvalitetu nodularnog lijeva. U procesu proizvodnje odlivene su dvije Y probe na kojima su provedena ispitivanja. Provedena su ispitivanja kemijskog sastava, mehaničkih svojstava i strukture nodularnog lijeva. Usporedbom rezultata svojstava, na početku i kraju lijevanja, uočava se kako pri kraju lijevanja dolazi do smanjenja u mehaničkih svojstava. Analiza strukture ukazuje kako se radi o željeznom lijevu s pretežno feritnom osnovom. Prema kraju lijevanja postupno raste udio perlita.

Abstract (english)

Ductile iron, or nodular cast iron, HRN-EN-GJS-400-15 is used in the automotive industry to make parts such as gears, differentials and axles due to its high strength and good toughness. Demands on quality are constantly growing, customers are setting higher and higher demands. In order for manufacturers to fulfill this, it is important to constantly control the chemical composition and minimize possible defects in the microstructure, and to modify production procedures in order to increase production and reduce costs. In this final paper, the production of ductile iron HRN-EN-GJS-400-15 is monitored, specifically the influence of the melt retention time in the casting ladle on the final quality of ductile iron. Two Y-shaped cast samples were cast in the production process. Chemical composition, mechanical properties and structure of nodular cast iron were tested. By comparing the results of the properties, at the beginning and end of casting, it is observed that near the end there is a drop in the mechanical properties. Analysis of the microstructure indicates that matrix of cast iron is predominantly ferrite base. Towards the end of the process, the proportion of pearlite gradually increases.

• Keywords: nodularni lijev; mehanička svojstva; struktura; ferit; Y proba; grafit
• Keywords (english): ductile iron; mechanical properties; structure; ferrite; Y-shaped cast samples; graphite
• Language: croatian
• URN:NBN: urn:nbn:hr:115:530295
• Study programme: Title: Vocational part-time study program Founding; Study programme type: professional; Study level: short; Academic / professional title: stručni/a pristupnik/ pristupnica ljevarstva (stručni/a pristupnik/ pristupnica ljevarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Embargoed access; Embargo expiration date: 2025-07-16
• Created on: 2024-07-02 11:42:33