Cold Sintering of Ni–Ag Nanocomposite Particles Produced by Electric Explosion of Wires

Abstract

77 Ni–23 Ag nanocomposite powder as well as nanopowders of Ni and Ag were produced by electric explosion of wires, and compacted specimens were made with the help of a cold sintering method at a high pressure. It is shown that electric explosion results in formation of mainly janus-nanoparticles of immiscible Ni and Ag metals with retention of nanostructure in consolidated bulk specimens. Microstructure and mechanical properties of cold sintered specimens prepared from as prepared and heat treated in hydrogen flow have been studied. It is ascertained that treatment of 70% dense compacts in hydrogen flow results in higher density and higher ductility of cold sintered specimens. Density of cold sintered at 3 GPa pressure 77 Ni–23 Ag and Ni specimens was reached about 95% from theoretical value whereas the density of Ag specimens is close to 100% of that. High strength was obtained under three-point bending tests and in compression tests.