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Automatic Classification of Graphite in Cast Iron

Published online by Cambridge University Press:  07 July 2005

Otávio da F.M. Gomes  and
Sidnei Paciornik
Otávio da F.M. Gomes
Affiliation:
Department of Materials Science and Metallurgy, Catholic University of Rio de Janeiro, Rua Marquês de S. Vicente, 225, sala 501L, Gávea, Rio de Janeiro, RJ, 22453-900, Brazil CETEM—Centre for Mineral Technology, Av Ipê, 900, Ilha do Fundão, Rio de Janeiro, RJ, 21941-590, Brazil
Sidnei Paciornik
Affiliation:
Department of Materials Science and Metallurgy, Catholic University of Rio de Janeiro, Rua Marquês de S. Vicente, 225, sala 501L, Gávea, Rio de Janeiro, RJ, 22453-900, Brazil
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Abstract

A method for automatic classification of the shape of graphite particles in cast iron is proposed. In a typical supervised classification procedure, the standard charts from the ISO-945 standard are used as a training and validation population. Several shape and size parameters are described and used as discriminants. A new parameter, the average internal angle, is proposed and is shown to be relevant for accurate classification. The ideal parameter sets are determined, leading to validation success rates above 90%. The classifier is then applied to real cast iron samples and provides results that are consistent with visual examination. The method provides classification results per particle, different from the traditional per field chart comparison methods. The full procedure can run automatically without user interference.

Keywords

cast ironautomatic classificationISO-945shape factorimage analysis
Type
TECHNIQUES FOR MICROSCOPY AND MICROANALYSIS
Information
Microscopy and Microanalysis , Volume 11 , Issue 4 , August 2005 , pp. 363 - 371
Copyright
© 2005 Microscopy Society of America

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References

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