EBSD Analysis of the Primary Austenite Grains in Lamellar Graphite Cast Iron

LÓPEZ, MARCOS G.; BREWER, LUKE N.; MASSONE, JUAN M.; BOERI, ROBERTO E.

Metallography, Microstructure, and Analysis

SPRINGER

Año: 2019 vol. 8 p. 386 - 392

2192-9262

This work investigates the size and morphology of the primary austenite grains present in lamellar graphite cast iron. Samples of lamellar graphite iron were cast and austempered during the post-solidifcation cooling stage in order to preserve part of the original austenite at room temperature. Electron backscatter difraction technique was applied to reveal the regions of diferent crystalline orientation of the austenite. The eutectic colonies and the last-to-freeze areas were also examined by color etching of the same regions previously analyzed by electron backscatter difraction. The results reveal that the solidifcation units of lamellar graphite iron are formed by austenite grains that include several eutectic colonies inside, all of which have the same crystalline orientation as the primary austenite grain. For all the samples studied, it can be confrmed that there are no eutectic colonies with a diferent crystalline orientation than that of the primary austenite dendrites.