Methods and apparatus for spray forming, atomization and heat transfer

Abstract

The present invention is directed to methods and apparatus that use electrostatic and/or electromagnetic fields to enhance the process of spray forming preforms or powders. The present invention also describes methods and apparatus for atomization and heat transfer with non-equilibrium plasmas. The present invention is also directed to articles, particularly for use in gas turbine engines, produced by the methods of the invention.

1 . A preform produced by a method for transferring heat between a first heat-transfer device and a workpiece, the method comprising producing a non-equilibrium plasma that transfers heat between the first heat-transfer device and the workpiece, wherein the first heat-transfer device is electrically charged or held at a potential, wherein the first heat-transfer device is mechanically separate from the workpiece, and wherein the first heat-transfer device comprises a heat sink or a heat source.  
     
     
         2 . The preform of  claim 1 , wherein the non-equilibrium plasma comprises a glow discharge or a cold corona discharge.  
     
     
         3 . The preform of  claim 1 , further comprising an external means for producing or maintaining the non-equilibrium plasma.  
     
     
         4 . The preform of  claim 1 , wherein the external means for producing or maintaining the non-equilibrium plasma comprises a thermionic emission, an RF electromagnetic radiation, an electromagnetic radiation, a magnetic field or an electron beam.  
     
     
         5 . The preform of  claim 1  which is a near net preform.  
     
     
         6 . An article of manufacture produced by a method for transferring heat between a first heat-transfer device and a workpiece, the method comprising producing a non-equilibrium plasma that transfers heat between the first heat-transfer device and the workpiece, wherein the first heat-transfer device is electrically charged or held at a potential, wherein the first heat-transfer device is mechanically separate from the workpiece, and wherein the first heat-transfer device comprises a heat sink or a heat source.  
     
     
         7 . The article of manufacture of  claim 6 , wherein the non-equilibrium plasma comprises a glow discharge or a cold corona discharge.  
     
     
         8 . The article of manufacture of  claim 6 , further comprising an external means for producing or maintaining the non-equilibrium plasma.  
     
     
         9 . The article of manufacture of  claim 6 , wherein the external means for producing or maintaining the non-equilibrium plasma comprises a thermionic emission, an RF electromagnetic radiation, an electromagnetic radiation, a magnetic field or an electron beam.  
     
     
         10 . The article of  claim 6  which is a component of a gas turbine engine.