High strength and erosion resistant powder blends

1. A method for preparing a composite comprising:

a) contacting about 40-70 wt % of a first fraction of ultra coarse tungsten carbide

with about 30-60 wt % a first fraction of cast carbide (CC) to form a blend, wherein the blend has a tap density of about 9-11.5 g/cm 3 ;

b) tapping the blend for at least 5 cycles; and

c) infiltrating the tapped blend with a copper containing alloy, thereby forming the composite,

wherein the formed composite exhibits volume loss of at least 20% lower as compared to a conventional GM-6 metal powder when measured accordingly to ASTM G65 and ASTM G76.

2. The method of claim 1 , wherein the first fraction of ultra-coarse tungsten carbide has a particle size from about 44 micrometers (325 mesh) to about 177 micrometers (80 mesh).

3. The method of claim 1 , wherein the first fraction of cast carbide has a particle size from 44 micrometers (325 mesh) to about 250 micrometers (60 mesh).

4. The method of claim 1 , wherein the first fraction of ultra-coarse tungsten carbide is present in an amount of about 60%.

5. The method of claim 4 , wherein the first fraction of cast carbide is present in an amount 40%.

6. The method of claim 4 , wherein the first fraction of ultra-coarse tungsten carbide has a particle size of at least about 44 micrometers (325 mesh).

7. The method of claim 4 , wherein the first fraction of cast carbide has a particle size of smaller than about 250 micrometers (60 mesh) but greater than about 125 micrometers (120 mesh).

8. The method of claim 1 , further comprising a step of mixing the blend with greater than 0 wt % to about 5 wt % of nickel prior to the step of infiltrating.

9. The method of claim 1 , further comprising a step of mixing the blend with greater than 0 wt % to about 5 wt % of iron prior to the step of infiltrating.

10. The method of claim 1 , further comprising a step of mixing the blend with one or more of: (a) from about 5 to about 25 wt % of a second fraction of ultra-coarse tungsten carbide having a particle size of greater than 63 micrometer (230 mesh) but smaller than 88 micrometer (170 mesh); (b) from about 5 to about 25 wt % of a third fraction of ultra-coarse tungsten carbide having a particle size of greater than 44 micrometer (325 mesh) but smaller than 63 micrometer (230 mesh); (c) from about 5 to about 25 wt % of a second fraction of cast carbide having a particle size of greater than 63 micrometer (230 mesh) but smaller than 88 micrometer (170 mesh); or d) from about 5 to about 25 wt % of a third fraction of cast carbide having a particle size of greater than 63 micrometer (230 mesh) but smaller than 125 micrometer (120 mesh) prior to the step of infiltrating.

11. The method of claim 1 , wherein the formed composite exhibits a Transverse Rupture Strength (TRS) of greater than 120 KSI.

12. The method of claim 1 , wherein the formed composite exhibits a volume loss under abrasion testing according to ASTM G65 of less than about 6 mm 3 .

13. The method of claim 1 , wherein the cast carbide has a plurality of particles having a microstructured surface.

14. The method of claim 1 , wherein the method comprises tapping the blend for at least 50 cycles.

15. The method of claim 14 , wherein the formed composite exhibits an average volume loss under abrasion testing according to ASTM G65 from 4.26 mm 3 to 4.86 mm 3 .

16. The method of claim 14 , wherein the formed composite exhibits an average Transverse Rupture Strength (TRS) of from 133.6 KSI to 144.6 KSI.

17. The method of claim 14 , further comprising a step of mixing the blend with greater than 0 wt % to about 5 wt % of nickel prior to the step of infiltrating.

18. The method of claim 14 , further comprising a step of mixing the blend with greater than 0 wt % to about 5 wt % of iron prior to the step of infiltrating.