Origin of differences in the excess volume of copper and nickel grain boundaries. (15th May 2016)

• Record Type: Journal Article
• Authors: Bean, Jonathan J.; McKenna, Keith P.
• Is Part Of: Acta materialia. Volume 110(2016)
• Page Start: 246
• Page End: 257
• Publication Date: 2016-05-15
• Subjects: Grain boundaries -- Copper -- Nickel -- Excess volume -- Atomistic modeling; Materials -- Periodicals; Materials science -- Periodicals; Materials -- Mechanical properties -- Periodicals; Metallurgy -- Periodicals; Chemistry, Inorganic -- Periodicals; 620.112
• DOI: 10.1016/j.actamat.2016.02.040
• Languages: English
• ISSNs: 1359-6454

Abstract

Abstract: The excess volume associated with grain boundaries is one of the primary factors driving defect segregation and diffusion which controls the electronic, mechanical and chemical properties of many polycrystalline materials. Experimental measurements of the grain boundary excess volume of fcc metals Cu and Ni have shown a difference of over 40%. The difference in lattice constant between Cu and Ni is only 3%, therefore this substantial difference is currently lacking explanation. In this article we employ a high throughput computational approach to determine the atomic structure, formation energy and excess volume of a large number of tilt grain boundaries in Cu and Ni. By considering 400 distinct grain boundary orientations we confirm that theoretically there is a systematic difference between the excess volumes in the two materials and we provide atomistic insight into the origin of the effect. Graphical abstract: