SIAMS Company, Yekaterinburg, Russia

T. A. Sivkova, Head of Engineering Department, e-mail: sivkova@siams.com

Yaroslavl State Technical University, Yaroslavl, Russia
A. G. Panov, Dr. Eng., Associate Prof., Prof., Dept. of Materials Technology, Standardization, and Metrology, e-mail: panov.ag@mail.ru
V. A. Ivanova, Dr. Eng., Associate Prof., Director of the Institute of Engineering and Mechanical Engineering, e-mail: ivanovava@ystu.ru

Modificator Research Center, Naberezhnye Chelny, Russia
N. G. Degtyareva, Metallurgist, e-mail: dnadegda@list.ru

Authors review the main issues related to assessment of the shape of individual graphite inclusions present on microscale specimens of cast iron, the said inclusions being projections of three-dimensional graphite phases to the face plane of the polished specimen. Paper features analysis of existing morphology assessment methods included in current standards, and analysis of terms used to describe microstructure of cast iron, demonstrating lack of a unified identification system for the shapes of graphite inclusions. SIAMS 800 Analyzer was used to digitize microstructure of over sixty industrial grade cast iron specimens featuring graphite inclusions of various shapes, and reference charts from Russian and international standards for controlling cast iron microstructure. An assessment of the shape of graphite inclusions was conducted. A scale was developed containing nine typical graphite inclusion shapes in the microstructure of cast irons, along with a text description and representative examples of inclusion contour images. The scale images include digitized fragments of the microstructure of working samples, represent a selection of typical graphite inclusions of each typical shape, and correspond to the developed text description and mathematical model characterizing the typical shape of a specific number. Thus, the scale—visually, and the image analysis system algorithm—automatically enable the identification and classification of graphite inclusions in cast irons by typical shapes without prior information on the grade of the cast iron being analyzed, for the purpose of quantitatively assessing the microstructure of the products being studied.

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