Dendrite-hardened amorphous and graphene-reinforced metal composites: Deformation mechanisms and strength characteristics

Abstract

The deformation mechanisms of hardened amorphous alloys and graphene-rernforced nanolayer composites are studied by molecular dynamics modeling (MD). It has been established (using CuZrAl as an example) that in amorphous alloys, under the influence of intense deformations accompanied by heat release, a dendritic nanophase is formed, which contributes to their strengthening. The dendntic nanophase hardens the alloys by tensile strength up to 20% at loads of 2300 MPa; the yield strength exceeds 1550 MPa. In graphene-rernforced nanolayer composites (Me/graphene, where Me = Ni, Al, Ti), a deformation mechanism of the transfer type is realized. The transfer-type mechamsm is the appearance of uniformly distnbuted microscopic cracks ("strain transfer") on the surface of the sample (along its entire length). In composites subjected to such deformation, the strength characteristics are significantly increased. The simulation results show good agreement (10 to 15%) with experimental literature data. © 2020 American Institute of Physics Inc.. All rights reserved.