Bulk copper-nanodiamond nanocomposites; Processing and properties

Correia, J, B.*; Livramento, V.*; Shohoji, Nobumitsu*; Tresso, E.*; Yamamoto, Kazunori; Taguchi, Tomitsugu; Hanada, Kotaro*; Osawa, Eiji*

Nanostructured metals and nanocomposites are ways to address the low hardness problem, provided the nanostructured material is thermally stable during processing and service. In the present research, Cu composite powders, with 5 to 30 at % nanodiamond, were consolidated into bulk samples. The copper-nanodiamond composite powders were vacuum encapsulated and extruded at 600 C. A significant proportion of the initial hardness in the powders is retained after extrusion. Transmission electron microscopy of the extruded material indicates good bonding between the nanodiamond particles and the copper matrix. Raman spectroscopy on the consolidated samples evidences the presence of graphite, possibly due to partial disintegration of ultradisperse nanodiamond agglomerates.