Microstructure Refinement of As-Cast Single Crystal Superalloys by Re-Solidification
Recently identified re-solidification behaviour of heavily alloyed single crystal super¬alloys has been incorporated into the Bridgman method. The process variables of resolidifcation temperature and mould withdrawal rate have been optimized. The microstructure, microporosity and eutectic phase fraction of re-solidified specimens were analyzed and compared with conventionally cast single crystal specimens. The potential advantage of this modified method has been illustrated by performing solution heat treatments on both re-solidified and normally cast specimens followed by eutectic phase fraction analysis.
T. Chandra, N. Wanderka, W. Reimers , M. Ionescu
S.R. Hegde et al., "Microstructure Refinement of As-Cast Single Crystal Superalloys by Re-Solidification", Advanced Materials Research, Vols. 89-91, pp. 250-255, 2010