Study of rapid grain boundary migration in a nanocrystalline Ni thin film

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Vol. 528; no. 3; pp. 1628 - 1635
• Main Authors: Kacher, Josh, Robertson, I.M., Nowell, Matt, Knapp, J., Hattar, Khalid
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 25.01.2011; Elsevier
• Subjects: Abnormal grain growth; Annealing; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Diffusion; Electron microscopy; Exact sciences and technology; Grain boundaries; Grain boundary migration; Grain growth; Lattice vacancies; Materials science; Nanocrystalline materials; Nanoscale materials and structures: fabrication and characterization; Nanoscale materials: clusters, nanoparticles, nanotubes, and nanocrystals; Nickel; Orientation; Physics; Pulsed laser deposited Ni; Structure of solids and liquids; crystallography; Texture; Thin films; Abnormal grain growth; Pulsed laser deposited Ni; Annealing; Electron microscopy; Grain growth; Growth rate; Pulsed laser deposition; Grain boundary migration; Grain orientation; Real time; Texture; EBSD; Thin films; Twin boundaries; Transmission electron microscopy; Transition elements; Nickel; Microstructure; Nanocrystal
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/j.msea.2010.10.109

▶ Abnormal growth is distributed randomly in the foil and initiates at different times. ▶ Growth occurs from seemingly uncorrelated regions of the grain boundary. ▶ Growth twins are created during all stages of abnormal grain growth. ▶ Grain growth patterns are qualitatively similar to a vacancy diffusion model. ▶ Grain boundaries and orientations evolve during growth to minimize system energy. Grain boundary migration associated with abnormal grain growth in pulsed-laser deposited Ni was studied in real time by annealing electron transparent films in situ in the transmission electron microscope. The resulting texture evolution and grain boundary types produced were evaluated by ex situ electron backscatter diffraction of interrupted anneals. The combination of these two techniques allowed for the investigation of grain growth rates, grain morphologies, and the evolution of the orientation and grain boundary distributions. Grain boundaries were found to progress in a sporadic, start/stop fashion with no evidence of a characteristic grain growth rate. The orientations of the abnormally growing grains were found to be predominately 〈111〉//ND throughout the annealing process. A high fraction of twin boundaries developed during the annealing process. The intermittent growth from different locations of the grain boundary is discussed in terms of a vacancy diffusion model for grain growth.