EBSD studies of microstructure and texture in Ni-Ti-Co shape memory strip and ribbon

摘要

The electron back scattered diffraction method was applied for carrying out detailed surface studies of the ternary Ni-Ti-Co alloy produced using melt-spinning and twin roll casting techniques. The samples were studied in the as-cast state without grinding or polishing. It was found that in the melt-spun ribbon apart from fine narrow columnar grains, that extended along the ribbon thickness, wider columnar grains parallel to the ribbon surface were also observed. These grains were textured along the {100}<011> orientation. The twin roll cast strip revealed more complex and inhomogeneous morphology of its surface. Mainly, the axes of the grains were oriented along two textural components: (100) for the fine grains and {100}(011} for the columnar grains parallel to the surface. In addition to the results obtained from the X-ray diffraction, the electron back scattered diffraction technique revealed the (111) fibre texture in the sample.