Deformation localization in a single crystal nickel-based superalloy oriented for multiple slip

• The nature of deformation bands in [011] sample were determined.
• Accurate orientation distribution and the route of lattice rotation were obtained.
• Continuous shearing of γ′ phase at small strain was observed in [011] sample.
• It's found that zig-zag dislocations couldn't shear matrix channels at room temperature.

The deformation and fracture in tension of a single crystal nickel-based superalloy were studied with relation to the crystallographic orientations. The [011] oriented sample exhibited significant heterogeneous deformation by asymmetric necking and deformation bands. On the contrary, the [111] one deformed in a macroscopically homogeneous way. Microstructure observation and EBSD analysis showed that those deformation bands in the [011] oriented sample were formed by concentration of particle shearing and led to lattice rotation of about 15°. Slip systems operating in the matrix channels caused the huge difference in the deformation behavior of the two orientations. Some related studies by other researchers carried out at different temperatures or stress states were also discussed.