Metallurgy, Vol. 59 No. 2, 2020.
Original scientific paper
Microstructure and properties of silicon alloyed compacted graphite irons (CGI)
A. Strkalj
orcid.org/0000-0002-7117-4687
; University of Zagreb, Faculty of Metallurgy, Sisak, Croatia
Z. Glavas
orcid.org/0000-0003-4116-3255
; University of Zagreb, Faculty of Metallurgy, Sisak, Croatia
Ilija Mamuzić
orcid.org/0000-0002-7117-4687
; Croatian Metallurgical Society, Zagreb, Croatia
Abstract
The microstructure, tensile properties and hardness of 25 mm thick compacted graphite iron samples alloyed with 3,01, 3,22, 3,61, 3,97 and 4,29 wt. % Si were analyzed in this paper. It was found that Si promotes and strengthens ferrite. Metallic matrix of compacted graphite iron sample alloyed with 3,01 wt. % Si consisted of 98,1 % ferrite and 1,9 % pearlite. Fully ferritic metallic matrix was obtained in compacted graphite iron samples alloyed with 3,22, 3,61, 3,97 and 4,29 wt. % Si. Nodularity varied from 8 to 13 %. Yield strength increased from 246 to 447 N/mm2, tensile strength increased from 318 to 496 N/mm2, hardness increased from 160 to 227 HBW, and elongation decreased from 3,6 to 1,6 % with an increase in Si content from 3,01 to 4,29 wt. %. Analyzed Si alloyed compacted graphite iron samples have a very uniform hardness and higher ratio Rp02/Rp02 than conventional ferritic, ferritic-pearlitic and pearlitic compacted graphite iron grades.
Keywords
compacted graphite iron; silicon; microstructure; tensile properties; hardness
Hrčak ID:
232359
URI
Publication date:
1.4.2020.
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