“Emergent grain boundaries at free surface impact a wide range of material properties but little is known about their atomic-scale behavior. Using scanning tunneling microscopy and calculations, we studied the structure of emergent grain boundaries at the surfaces of planar nanocrystalline copper (111) films and bicrystals. We show that for a wide range of misorientation angles there exists a strong energetic preference for boundary cores to lie along close-packed planes that leads to the restructuring of emergent grain boundaries at free surfaces.”

Read the paper and see the full list of authors in Acta Materiala.