Structural effect of two-dimensional BNNS on grain growth suppressing behaviors in Al-matrix nanocomposites.

ABSTRACT: While nanocrystalline (NC) metals exhibit superior strength to conventional microcrystalline metals, their thermal instability has hampered their application at high temperatures. Herein, two-dimensional (2D) boron nitride nanosheets (BNNS) are proposed as reinforcement to enhance the strength as well as the thermal stability of NC Al. The strength of pure Al was increased from 80 to 468 MPa by refining its grains from ~600 to ~40 nm, and it was further enhanced to 685 MPa by incorporating 2 vol% of BNNS. Moreover, the small amount of BNNS was found to effectively suppress grain growth of NC Al at 580 °C (~0.9 T_m, where T_m is the melting point of Al), which prevented a strength drop at high temperature. Finally, the Zener pinning model in conjunction with phase-field

SUBMITTER: Nam S 

PROVIDER: S-EPMC5785491 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature