The Gnps Evolution and Interface Reaction Mechanism of Gnps/Ta15 Composites by Pre-Sintering and Canned Hot Extrusion

Abstract

The interface between GNPs and Ti matrix was crucial for the properties of GNPs/TA15 composites. Thus, it was necessary to deeply investigate the interface reaction mechanism. Herein, the GNPs/TA15 composites were fabricated by pre-sintering and canned hot extrusion. During pre-sintering, the chemical reaction between GNPs and Ti matrix occurred, and the TiC particles formed at the interface. It is predicted that the chemical bonding strength was much higher than van der Waals forces. Therefore, during extrusion, the outer layers of GNPs would flow with the Ti matrix. And then, the relative locations changed clearly among the layers of GNPs. Namely, a new interface appeared along with the deformation of GNPs and Ti matrix. Immediately, the chemical reaction also occurred at the new interface, resulting in the formation of TiC plates. Similarly, the TiC particles would grow up further. A special interface was obtained, i.e., the nano-TiC plates distributed among large TiC particles. Additionally, the ultimate strength of TMC2 and TMC3 decreased significantly with the severe interface reaction. This work reveals the evolution of GNPs and reports the interface reaction mechanism of deformed GNPs/Ti composites.

Keywords: GNPs, Ti matrix, TiC, interface reaction mechanism, interface evolution.