Wire arc spray system using composite wire for porous coating, and related method

1. A wire arc spray system comprising:

a composite wire including a core region having a first material and a cladding surrounding the core region,

wherein the cladding includes a metal, and the first material includes a polymer;

a first wire delivery apparatus physically connected to the composite wire and configured to deliver the composite wire to an arc point;

a second wire delivery apparatus configured to deliver a non-composite wire to the arc point;

a propelling gas source for delivering a propelling gas to the arc point;

an electrical source configured to create a first electrical polarity in the composite wire and a second electrical polarity in the non-composite wire, the second electrical polarity being opposite to the first electrical polarity;

a mover adapted to control a distance between the arc point and a surface to be coated; and

a controller configured to provide instructions to at least one of the mover, the electrical source, the propelling gas source and the first and second wire delivery apparatuses to propel molten droplets of a heated material on to the surface to be coated,

wherein the heated material is created by an arcing of the composite wire and the non-composite wire at the arc point, and

wherein the propelling of the molten droplets of the heated material creates a porous metal coating on the surface to be coated.

2. The wire arc spray system of claim 1 , wherein the controller is further configured to provide instructions to substantially vaporize the polymer by adjusting at least one of: a voltage level at the arc point, a current level at the arc point, a volume of the propelling gas, a pressure of the propelling gas, a feed rate of the composite wire, a feed rate of the non-composite wire, and the distance between the arc point and the surface to be coated.

3. The wire arc spray system of claim 1 , wherein the non-composite wire is a metal wire and the first material further includes a polyester in the form of a powder having particles having a size of approximately 1 nanometer to approximately 100 nanometers.

4. The wire arc spray system of claim 3 , wherein the propelling gas is a combustion-based gas.

5. The wire arc spray system of claim 4 , wherein the propelling gas source includes a combustion chamber.

6. The wire arc spray system of claim 5 , wherein the controller is further configured to adjust a volume and a pressure of the propelling gas flow by controlling a combustion process in the combustion chamber.

7. The wire arc spray system of claim 4 , wherein the combustion-based gas further includes a gas selected from the group consisting of: hydrogen, oxygen, acetylene, propylene, and kerosene.

8. The wire arc spray system of claim 1 , wherein the first material further includes a metal selected from the group consisting of: aluminum, zinc, and tin.

9. The wire arc spray system of claim 1 , wherein the controller is further configured to provide instructions to control a porosity of the metal coating by adjusting at least one of: a voltage level at the arc point, a current level at the arc point, a volume of the propelling gas, a pressure of the propelling gas, a feed rate of the composite wire, a feed rate of the non-composite wire, and the distance between the arc point and the surface to be coated.

10. The wire arc spray system of claim 1 , wherein the core region is configured in a pattern adapted to provide the porous metal coating.

11. The wire arc spray system of claim 1 , wherein the polymer has a low melting temperature relative to the cladding and the non-composite wire.

12. The wire arc spray system of claim 1 , wherein the first material is a solid.