Verbundkoerper aus Kupfer oder einer Kupferlegierung mit eingelagertem Carbon Nanotubes und Verfahren zur Herstellung eines solchen Koerpers sowie Verwendung des Verbundkoerpers

(A1) Die Erfindung betrifft einen Verbundkoerper aus Kupfer oder einer Kupferlegierung mit eingelagerten Carbon Nanotubes, ein Verfahren zur Herstellung eines solchen Koerpers sowie die Verwendung dieses Koerpers. Erfindungsgemaess liegt der CNT-Anteil zwischen 0,1 Gew.-% und 1,5 Gew.%. Der Verbundkoerper ist durch Sintern oder durch Abkuehlen einer CNTs in einer zumindest weitgehend homogenen Verteilung enthaltenden Metallschmelze herstellbar. Vorzugsweise wird der Verbundkoerper als Bauteil fuer Elektroanschluesse oder in Hochtemperaturanlagen oder Hochdruckanlagen verwendet.

DE 102008056750 A1 UPAB: 20100604 NOVELTY - The composite is made from copper or copper alloy and contains embedded carbon nanotubes (CNT). It is formed by sintering or by cooling molten metal containing uniformly-distributed CNT. For production by sintering or hot-pressing, the copper (or copper alloy) powder preferably has a particle size of 0.1-50 mu m. It is mixed with 0.1-1.0 wt% CNT. It is pre-compressed. It is then sintered or hot-pressed under a pressure of 30-50 MPa at 750-800 degrees C. DETAILED DESCRIPTION - At least when above 600 degrees C, the sintering or hot-pressing is carried out in an inert gas atmosphere. In the alternative method, the copper (or copper alloy) is heated above its melting point in a crucible induction furnace. Together with the distributed CNT, the metal is cooled and solidified. The CNTs are added into the molten metal. The metal, in powder form, may be mixed with the CNTs and then introduced into the induction furnace. Alternatively a Cu-CNT composite is formed using the powder-metallurgy route with sintering. If appropriate further Cu or Cu alloy is added in powder- or solid form, then it is transferred to the crucible induction furnace for melting and subsequent cooling. Cooling takes place at room temperature. Alternatively, it is imposed at the rate of 10-1,000 K/s. For cooling, flowing fluids, liquid gases (preferably nitrogen) or liquid baths are employed. The finished sintered- or hot-pressed object is deformed by e.g. rolling, extrusion or drawing. AN INDEPENDENT CLAIM IS INCLUDED FOR the method of manufacture. USE - To manufacture a composite material containing copper and embedded carbon nanotubes. The composite is used to make electrical connections passing heavy currents of up to 5000A. It is used to make bearing components for high temperature- or high pressure plants. (All claimed) ADVANTAGE - Carbon nanotubes are known to have high values of: electrical conductivity, extensibility and yield point. Their density is low. The thermal conductivity is exceptional. It is found that the hardness of copper, normally quoted as 35HB, is increased to 58 HB in the composite form containing a 0.5 wt% addition of nanotubes. The thermal conductivity is also improved. Electrical conductivity of the composite is optimized. A number of graphs in the disclosure, show how nanotube addition varies electrical and mechanical properties of the composite. In mechanical applications, the composite acts as a self-lubricating metal. It is durable in high temperature- and high pressure applications.