Creep of single-crystals of nickel-base ?-alloy at temperatures between 1150 °C and 1288 °C

A ?-analogue of the superalloy CMSX-4 that does not contain strengthening ??-phase and only consists ?-solid solution nickel has been designed, solidified as single-crystals different orientations, tested under creep conditions in temperature range between 1150 1288 °C. The tests have revealed a very high anisotropy this alloy, was previously found for at supersolvus This could be explained by dominance 011111 octahedral slip. Furthermore, analysis data yielded value activation energy, Qc?442 kJ/mol, which correlates with energy Re diffusion Ni. supports hypothesis dislocation motion ?-matrix Re-containing superalloys is controlled atoms segregating core. Norton stress exponent n close to 5, typical pure metals their alloys. absence ??-reprecipitation after high-temperature facilitates microstructural investigations. It shown EBSD deformation results an increasing misorientation existing low angle boundaries. In addition, according TEM, new boundaries appear due reactions a/2011 mobile dislocations knitting networks.