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 R_p02/R_p02 than conventional ferritic, ferritic-pearlitic and pearlitic compacted graphite iron grades.

Keywords

compacted graphite iron; silicon; microstructure; tensile properties; hardness

Hrčak ID:

232359

URI

https://hrcak.srce.hr/232359

Publication date:

1.4.2020.

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