Welding rods including PCD particles and methods of forming such welding rods

1. A welding rod for use in applying hardfacing to a surface of a tool, comprising:

an elongated, generally cylindrical body comprising a metal matrix material; and

particles of polycrystalline diamond material carried by the elongated, generally cylindrical body, the particles of polycrystalline diamond material comprising a plurality of inter-bonded diamond grains, wherein the inter-bonded diamond grains define a substantially continuous open-pore network within the polycrystalline diamond material.

2. The welding rod of claim 1 , wherein the elongated, generally cylindrical body comprises a hollow tube, and wherein the particles of polycrystalline diamond material are disposed within the hollow tube.

3. The welding rod of claim 1 , further comprising additional hard particles, wherein the additional hard particles comprise particles selected from the group consisting of a carbide material, a boride material, a nitride material, and non-polycrystalline diamond grit.

4. The welding rod of claim 3 , wherein the additional hard particles comprise hard particles selected from the group consisting of tungsten carbide, titanium carbide, tantalum carbide, silicon carbide, titanium boride, and silicon nitride.

5. The welding rod of claim 1 , wherein the elongated, generally cylindrical body comprises a substantially solid cylinder that includes the particles of polycrystalline diamond material embedded within the matrix material.

6. The welding rod of claim 1 , wherein the particles of polycrystalline diamond material comprise fragmented portions of polycrystalline diamond material.

7. The welding rod of claim 1 , wherein the particles of polycrystalline diamond material are at least substantially planar, have an average particle diameter between about 0.25 millimeter and about 7.0 millimeters, and have an average particle thickness between about 0.1 millimeter and about 5.0 millimeters.

8. A method of forming a welding rod, comprising:

breaking down a layer of polycrystalline diamond material of a cutting element to form particles of the polycrystalline diamond material; and

forming an elongated, generally cylindrical body comprising a metal matrix material and the particles of the polycrystalline diamond material.

9. The method of claim 8 , wherein forming an elongated, generally cylindrical body comprises at least one of a forging process, a casting process, and an extrusion process.

10. The method of claim 8 , wherein forming an elongated, generally cylindrical body comprises:

forming a generally hollow cylindrical tube; and

disposing the particles of polycrystalline diamond material within the hollow cylindrical tube.

11. The method of claim 10 , further comprising sealing at least one end of the elongated, generally cylindrical body.

12. The method of claim 8 , wherein forming an elongated, generally cylindrical body comprises disposing fragmented portions of polycrystalline diamond material within the metal matrix material.

13. The method of claim 8 , further comprising leaching catalyst material from interstitial spaces between the plurality of inter-bonded diamond grains to form a continuous open-pore network within the polycrystalline diamond material.

14. The method of claim 8 , wherein breaking down a layer of polycrystalline diamond material of a cutting element to form the particles of the polycrystalline diamond material comprises at least one of crushing, milling, and grinding the layer of polycrystalline diamond material of the cutting element.

15. A welding rod, comprising:

an elongated body comprising a continuous metal matrix material; and

particles of polycrystalline diamond material disposed within the elongated body, the particles of polycrystalline diamond material comprising a plurality of inter-bonded diamond grains wherein the inter-bonded diamond grains define a substantially continuous open-pore network within the polycrystalline diamond material.

16. The welding rod of claim 15 , wherein the elongated body comprises at least one outer wall, and wherein the particles of polycrystalline diamond material are disposed within a volume at least partially defined by the at least one outer wall.

17. The welding rod of claim 15 , further comprising additional hard particles, wherein the additional hard particles comprise hard particles selected from the group consisting of tungsten carbide, titanium carbide, tantalum carbide, silicon carbide, titanium boride, and silicon nitride.

18. The welding rod of claim 15 , wherein the elongated body comprises a substantially solid body that includes the particles of polycrystalline diamond material embedded within the continuous matrix material.

19. The welding rod of claim 15 , wherein the particles of polycrystalline diamond material comprise fragmented portions of polycrystalline diamond material.

20. The welding rod of claim 15 , wherein the particles of polycrystalline diamond material are at least substantially planar, have an average particle diameter between about 0.25 millimeter and about 7.0 millimeters, and have an average particle thickness between about 0.1 millimeter and about 5.0 millimeters.