Simulation of thermal analysis applied to the description of the solidification of hypereutectic SG irons

Abstract

AbstractThermal analysis is widely used in foundry to control melt preparation of cast irons. Its great versatility explains that many attempts have been made in the past to use it not only for controlling the composition but also to check the melt treatment in relation with the expected microstructure. Moreover, it has been claimed that micro-macro modelling which couples a description of the formation of the microstructure and a simulation of the heat transfer and temperature evolution during solidification could be of some help to analyse the results of thermal analyses. The present work was undertaken in this line of research.This paper reports firstly an experimental study on the solidification of hypereutectic spheroidal graphite cast irons with various amounts of inoculant added. Thermal analyses were performed for each melt preparation and relations between a few characteristics of the cooling curves and the final microstructure were looked for. Secondly, the simulation of the thermal analysis experiments was performed. For this purpose, use has been made of a physical model recently developed to describe the solidification of hyper as well as hypoeutectic alloys. Simulated cooling curves and nodule count have been described and compared to the experimental ones.Keywords: spheroidal graphite (SG) cast ironsthermal analysissolidificationmicrostructure modeling