Thermal stability of Cr-Cr3Si eutectic microstructures

The thermal stability of Cr-Cr3Si lamellar eutectic composites was investigated at temperatures up to 1400 degrees C. In drop-cast Cr-Cr3Si, coarsening was found to be interface controlled. The coarsening rate could be reduced by microalloying with Ce and Re, two elements which were chosen because they were expected to segregate to the Cr-Cr3Si interfaces. Similarly, directional solidification, whichc is also expected to lowere the Cr-Cr3Si interfacial energy, was found to dramatically decrease the coarsening rate. (C) 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.