On catalytic action of nickel, copper and nickel-copper alloy in graphite-diamond phase transformation

Abstract

163-169Synthetic diamonds were grown by subjecting spectroscopic grade graphite to static high pressures and temperatures in the presence of copper, nickel and their alloy namely monel as catalyst solvents. Diamond formation in the presence of conventional  catalysts (nickel and monel) takes place immediately after their melting temperatures. However, the catalytic action of copper was found to be altogether different from the well known iron group metals and al loys (nickel and monel) in that it is found to be inert with graphite near its melting temperature, however at much higher temperature it becomes an active catalyst and leads to diamond formation. The graphite-diamond phase transformation in presence of these catalysts is discussed based on experimental evidences.</span