XRD, XPS and SEM characterisation of Cu–NbC nanocomposite produced by mechanical alloying

Spark plasma sintering of mechanically alloyed in situ copper–niobium carbide composite

“…Copper-based metal matrix composites reinforced with hard phase particles of carbides, oxides, and borides have become an attractive area of research [3][4][5][6][7][8]. Copper composites have a wide range of applications in the electronics field such as for production of electrodes for electrical spot welding, sliding electrical contacts and high-performance switches [1,[9][10][11], enhancement of thermal conductivity such as heat exchanger, and in actively cooled components [12] and the wear industry [4,5,13].…”

Partially oxidized niobium carbonitride as a non-platinum catalyst for the reduction of oxygen in acidic medium

“…9(b) and (d), the as-prepared NbC 0.5 N 0.5 had peaks identified as NbC (282.8 eV) [38] and NbN (397.2 eV) [39]. The binding energies of Nb 3d 5/2 peaks corresponding to NbC and NbN were 203.7 eV [40] and 203.8 eV [41], respectively. Niobium forms oxides in various oxidation states, i.e., NbO 2 (Nb 4+ ) at a binding energy of 205.5-206.0 eV, and Nb 2 O 5 (Nb 5+ ) at 207.0-207.6 eV [40,42].…”

“…The binding energies of Nb 3d 5/2 peaks corresponding to NbC and NbN were 203.7 eV [40] and 203.8 eV [41], respectively. Niobium forms oxides in various oxidation states, i.e., NbO 2 (Nb 4+ ) at a binding energy of 205.5-206.0 eV, and Nb 2 O 5 (Nb 5+ ) at 207.0-207.6 eV [40,42]. Three peaks were superimposed in the Nb 3d 5/2 spectrum of the NbC 0.5 N 0.5 .…”

Effects of milling time on hardness and electrical conductivity of in situ Cu–NbC composite produced by mechanical alloying

“…Such materials have recently attracted a great deal of attention due to their unique properties compared to bulk materials. Marques et al [4] has succeed in producing Cu-NbC nanocomposite by mechanical alloying which involved repeated welding, fracture and re-welding of the reactant of mixed powders in a high-energy ball mill. As mentioned by Boytsov et al [5] microstructure characteristic of ball milling metallic copper powder depends on the milling condition, such as ball to powder ratio, rotation velocity of vial and disc, powder shocks and milling duration.…”

“…The composite powder was characterized after each milling time and not subjected to further consolidation processing [1,4,7]. Little information is available regarding the effects of milling parameter on physical and mechanical properties of the in situ copper-based composite.…”