Utjecaj debljine stijenke odljevka na morfologiju grafita u feritnom silicijem očvrsnutom nodularnom lijevu

master's thesis

• Title (english): Effect of casting wall thickness on graphite morfology in ferritic ductile iron strengthened by silicon
• Author: Ante Severinski
• Mentor: Zoran Glavaš (mentor)
• Committee member: Stjepan Kožuh (predsjednik povjerenstva)
• Committee member: Zoran Glavaš (član povjerenstva)
• Committee member: Martina Lovrenić-Jugović (član povjerenstva)
• Granter: University of Zagreb; Faculty of Metallurgy; Sisak
• Defense date and country: 2018-07-26, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Metallurgy

Abstract

U ovom diplomskom radu analiziran je utjecaj debljine stijenke odljevka na morfologiju grafita u feritnom silicijem očvrsnutom nodularnom lijevu. Ukupno su izrađene tri taline sa sljedećim udjelima silicija: 3,11, 3,8 i 4,22 %. Analiza je provedena na odljevcima stepenastog oblika koji sadrže sedam stijenki različite debljine: 3, 12, 25, 38, 50, 75 i 100 mm. Dobiveni rezultati pokazuju da se broj nodula/mm2 i nodularnost smanjuju s povećanjem debljine stijenke. Povećanje udjela silicija od 3,11 do 4,22 % rezultiralo je povećanjem broja nodula/mm2 i nodularnosti u stijenkama debljine 3, 12, 25 i 38 mm. Međutim, u debelim stijenkama, tj. stijenkama debljine 50, 75 i 100 mm povećanje udjela silicija rezultiralo je smanjenjem broja nodula/mm2 i nodularnosti. U tim stijenkama, s porastom udjela silicija povećavao se broj jako sitnih nepravilnih grafitnih čestica i nakupina čestica grafita koje po obliku sliče chunky grafitu.

Abstract (english)

Effect of the casting wall thickness on the graphite morphology in ferritic ductile iron strengthened by silicon was analysed in this graduate thesis. Three melts with the following silicon contents were made: 3.11, 3.8 and 4.22 %. The analysis was carried out on stepped castings containing seven different wall thicknesses: 3, 12, 25, 38, 50, 75, and 100 mm. Obtained results show that the nodule count and nodularity decrease with increasing wall thickness. The increase in silicon content from 3.11 to 4.22 % resulted in an increase in nodule count and nodularity in wall thicknesses of 3, 12, 25 and 38 mm. However, in thick walls, i.e. in wall thicknesses of 50, 75 and 100 mm, the increase in silicon content resulted in a decrease in nodule count and nodularity. In these walls, the number of very small irregular graphite particles and clusters of graphite particles that look like chunky graphite increased with the increase in silicon content.

• Keywords: feritni silicijem očvrsnuti nodularni lijev; mikrostruktura
• Keywords (english): ferritic ductile iron strengthened by silicon; microstructure
• Language: croatian
• URN:NBN: urn:nbn:hr:115:874347
• Study programme: Title: Graduate study program Metallurgy; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka metalurgije (magistar/magistra inženjer/inženjerka metalurgije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2018-08-23 07:28:06