摘要
Precipitation of topologically close-packed phases in a Re-containing Ni-base single crystal superalloy was studied under elevated temperature by in situ transmission electron microscopy.Above 1150℃,a new intergrowth structure called C phase was found within μ phase with a defined crystallographic orientation relationship.Elements mapping analysis reveals that C phase has a similar element composition as μ phase,but contains a lower level of Cr,W and Re.With increasing temperature,the proportion of C phase increases gradually.At 1250℃,C phase becomes the dominant precipitate.It is demonstrated that C phase is more thermodynamically stable than μ phase above 11509 that leads to an intergrowth pathway from μ phase to C phase.
Precipitation of topologically close-packed phases in a Re-containing Ni-base single crystal superalloy was studied under elevated temperature by in situ transmission electron microscopy.Above 1150℃,a new intergrowth structure called C phase was found within μ phase with a defined crystallographic orientation relationship.Elements mapping analysis reveals that C phase has a similar element composition as μ phase,but contains a lower level of Cr,W and Re.With increasing temperature,the proportion of C phase increases gradually.At 1250℃,C phase becomes the dominant precipitate.It is demonstrated that C phase is more thermodynamically stable than μ phase above 11509 that leads to an intergrowth pathway from μ phase to C phase.
基金
financially supported by the National Natural Science Foundation of China (Grant No.51271186)
the Hundred Talents Program of the Chinese Academy of Sciences
