Influencia de la microestructura de partida y la composición química en la ferritización y perlitización de hierros nodulares

Harold Machado; Mateo Montoya; Ricardo Aristizábal

doi:10.17533/udea.rcm.342060

Authors

Harold Machado University of Antioquia
Mateo Montoya University of Antioquia
Ricardo Aristizábal Universidad de Antioquia

DOI:

https://doi.org/10.17533/udea.rcm.342060

Keywords:

ductile iron, annealing, normalizing, microsegregation, austenization, isothermal treatment, density nodule

Abstract

In this work the effect of the chemical composition, starting microstructure, nodule count and heat treatment temperatures in obtaining fully ferritic or fully pearlitic matrices for four ductile iron alloys with different nickel and copper contents were studied. Calculations with ThermoCalc®, scanning electron microscopy and optical microscopy were used to determine the optimum temperatures and times of the heat treatments to obtain the desired matrices. The results showed that the chemical composition affects the annealing temperature and the holding time, especially when you have copper in the alloy, making it difficult to dissolve the pearlite. Similarly, there is a change in the count of nodules in ferritized alloys. It was also found that the temperature range for normalization without the presence of ferrite in the matrix is between 460-500 ° C, having a variation in interlaminar spacing due to difference between the heat treatment temperature and the eutectoid temperature.

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Author Biographies

Harold Machado, University of Antioquia

PhD student, Pyrometallurgical and Materials Research Group (GIPIMME), University of Antioquia, Medellín, Colombia.

Mateo Montoya, University of Antioquia

PhD student, Pyrometallurgical and Materials Research Group (GIPIMME), University of Antioquia, Medellín, Colombia.

Ricardo Aristizábal, Universidad de Antioquia

PhD student, Pyrometallurgical and Materials Research Group (GIPIMME), University of Antioquia, Medellín, Colombia.

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