摘要
The intermetallic compound such as Ni_(2)Si has a brittle nature.Therefore,monolithic intermetallic compounds have not yet been prepared by mechanical downsizing.During mechanical drawing of bulk CuNi_(2)Si alloy at room temperature,we observed more than 400%plastic elongation of hard and brittle Ni_(2)Si intermetallic nano-fibers.The calculation based on the density functional theory reveals that the fully coherent interface induces strain on the intermetallic compound surrounded by the matrix,and lowers the intrinsic stacking fault energy below the level required to break an interatomic bond.The new interface between the Ni_(2)Si intermetallic and Cu matrix formed by the plastic deformation is as stable as the original coherent interface formed by precipitation,and the activation energy of the newly formed interface to slip is similar to that of the Cu matrix.All of these make plastic deformation of brittle Ni_(2)Si intermetallic possible by slip without failure.
基金
the financial support from the National Research Foundation of Korea(Nos.2020M3D1A2098962,2018R1A5A6075959,2014M3A6B1060886)
Technology Innovation Program funded By the Ministry of Trade,Industry&Energy,Korea(No.20010384)
Fundamental Research Program of the Korean Institute of Materials Science(No.PNK7730)
Cooperative program of Professional Development Consortium for Computational Materials Scientists in IMR,Tohoku University(No.20S0513)。