Revealing the influence of solute segregation on the stability and strength of Cu Σ11 [110](113) symmetrical tilt grain boundary via first-principles investigation

Abstract

The stability and strength of the grain boundary (GB) structure are critical for the practical application of nanocrystals. This study systematically calculates the impact of the segregation of 26 transitional alloy elements on Cu Σ11 [110](113) GB using the first-principle theoretical calculation method. The research findings demonstrate that there is a parabolic connection between atomic number and segregation energy of TM elements in the same period. In addition to Fe, Co, and Ni, all other 23 elements have the potential to segregate to Cu GB, with Zr exhibiting the strongest segregation tendency. The difference in atomic radius and electronegativity between solute atoms and copper atoms strongly affects the segregation tendency, the greater the difference, the greater the tendency for segregation. The segregation energy of solute segregation has strong linear correlation with its GB energy, and the stronger the segregation ability, the more stable the GB. Except for Zn, Ag, Cd, and Au, other 19 alloying elements can increase the strength of GB. Electronic analysis indicates that the strengthening and embrittlement of solutes are primarily related to the accumulation and consumption of electrons near GB and the bonding between atoms.

Keywords

• Density functional theory
• Grain boundary
• Segregation
• Strength
• Tensile