Effects of Temperature and Stress on Microstructural Evolution during Creep Deformation of Ru‐free and Ru‐containing Single Crystal Superalloys

Abstract

Effects of temperature and stress on microstructural evolution of the two experimental alloys at various conditions have been studied after creep deformation. The topological inversion has been observed under certain conditions, and it is more pronounced at the same temperature but lower stress levels. Ru additions support the topological inversion, especially at very high temperature. In addition, the γ/γ′ interfacial networks have been observed by SEM after deep etching. Moreover, the a<101> superdislocations only present at relatively high temperature in this work, however, it is expected at each temperature at stresses above a critical level. At last, the a<010> superdislocations have also been identified and it is considered more energetically favorable than that of the a<101> superdislocations.