Cold spray system nozzle

1. A method of using a powder spray nozzle comprising:

spraying a powder onto a substrate through a nozzle; and

supplying a process gas heated to a temperature between 50 and 280° C. from a process gas supply through the nozzle together with the powder,

wherein the nozzle comprises:

an inlet portion having an inlet diameter and an inlet length;

an outlet portion having outlet diameter and an outlet length; and

an interface region between the inlet portion and the outlet portion having an interface diameter,

wherein a ratio of the inlet diameter to the inlet length is a range of about 0.15 to 0.5.

2. The method of claim 1 , wherein the powder comprises a metal or metal alloy powder which flows through the nozzle in a turbulent flow regime.

3. The method of claim 1 , wherein the temperature of the heated process gas is between 100 and 180° C.

4. The method of claim 1 , wherein an exit velocity of the process gas from the nozzle is greater than mach 1.

5. The method of claim 1 , wherein the process gas is supplied at a pressure of less than 20 bar.

6. The method of claim 1 , wherein the process gas is supplied at a pressure of 2 to 14 bar and wherein the powder comprises a copper indium gallium alloy.

7. The method of claim 6 , wherein the process gas is supplied at a pressure of 2 to 8 bar.

8. The method of claim 1 , wherein the powder comprises a copper indium gallium alloy and the substrate comprises a sputtering target support.

9. The method of claim 8 , wherein the sputtering target support comprises a cylindrical support for a rotary sputtering target and the powder forms a copper indium gallium sputtering layer deposited on an outer surface of the cylindrical support.

10. The method of claim 8 , wherein the sputtering target support comprises a cylindrical support for a rotary sputtering target and the powder forms a copper indium gallium sputtering layer deposited on an outer surface of the cylindrical support, and wherein a throat diameter of the nozzle is between 3 and 12 mm.

11. The method of claim 1 , further comprising mixing the process gas heated to the temperature between 50 and 280° C. with the powder prior to the step of providing the process gas through the nozzle together with the powder.

12. The method of claim 6 , wherein the process gas consists essentially of air.

13. The method of claim 1 , wherein the process gas consists essentially of air.

14. The method of claim 1 , wherein the process gas substantially excludes helium.