Mo-Cu Composite powder
A Mo—Cu composite powder is provided which is comprised of individual finite particles each having a copper phase and a molybdenum phase wherein the molybdenum phase substantially encapsulates the copper phase. The composite powder may be consolidated by conventional P/M techniques and sintered without copper bleedout according to the method described herein to produce Mo—Cu pseudoalloy articles having very good shape retention, a high sintered density, and a fine microstructure.
1. A method of making a CuMoO 4 -based composite oxide powder comprising:
(a) forming a mixture of a molybdenum oxide and a copper oxide, the molybdenum oxide being selected from ammonium dimolybdate, ammonium paramolybdate, or molybdenum dioxide; and
(b) firing the mixture at a temperature and for a time sufficient to form the CuMoO 4 , based composite oxide.
2. The method of claim 1 wherein a stoichiometric excess of up to 4 wt. % copper oxide is added to the mixture.
3. The method of claim 1 wherein the copper oxide is selected from cuprous oxide or cupric oxide.
4. The method of claim 1 wherein the CuMoO 4 -based composite oxide has a general formula of CuMoO 4 +xMoO 3 where x is from about 29 to 0.
5. The method of claim 1 wherein the mixture is fired at a temperature from about 650° C. to about 750° C. for about 5 hours.
6. The method of claim 5 wherein a stoichiometric excess of up to 4 wt. % copper oxide is added to the mixture.
7. The method of claim 6 wherein the copper oxide is selected from cuprous oxide or cupric oxide.
8. The method of claim 5 wherein the CuMoO 4 -based composite oxide has a general formula of CuMoO 4 +xMoO 3 where x is from about 29 to 0.