In-situ observation of Ni-Co based wrought superalloy high-temperature deformation: lattice rotation and grain boundary response

Abstract

The sensitivity of grain boundary (GB) cracks often limits the high-temperature plasticity of superalloys. The 750 ℃ tensile deformation of fine-grained Ni-Co based wrought superalloys was observed in situ using a scanning electron microscope (SEM) equipped with an electron backscatter diffraction (EBSD) probe to clarify the texture formation and GB response. The GB stress concentration depends on the grain orientation and slip system alignment on both sides. This reflects the ability of GBs to cope with deformation incompatibility. This study provides valuable insights for predicting the failure of polycrystalline superalloys and offers new ideas for microstructure evaluation and GB design.

Keywords

• Superalloy
• In-situ
• grain boundaries
• slip
• high-temperature deformation