Tool with a large volume of a superhard material

1. A tool, comprising:

a wear-resistant base suitable for attachment to a driving mechanism and a hard tip attached to a second carbide segment which is attached to an interfacial surface of the base;

the tip comprising a first cemented metal carbide segment bonded to a superhard material at a non-planar interface;

the tip comprising a height of 4 to 10 mm and a curved working surface opposite the interfacial surface;

wherein a volume of the superhard material is about 75% to 150% of a volume of the first cemented metal carbide segment; and

wherein the first end of the second segment comprises a cross sectional thickness of about 6 to 20 mm and the second end of the second segment comprises a cross sectional thickness of 25 to 40 mm.

2. The tool of claim 1 , wherein the first cemented metal carbide segment comprises a diameter of 9 to 18 mm.

3. The tool of claim 1 , wherein the superhard material is selected from the group consisting of polycrystalline diamond, vapor-deposited diamond, natural diamond, cubic boron nitride, infiltrated diamond, layered diamond, diamond impregnated carbide, diamond impregnated matrix, silicon bonded diamond, and combinations thereof.

4. The tool of claim 1 , wherein the superhard material may be sintered with a catalytic element selected from the group consisting of iron, cobalt, nickel, silicon, hydroxide, hydride, hydrate, phosphorus-oxide, phosphoric acid, carbonate, lanthanide, actinide, phosphate hydrate, hydrogen phosphate, phosphorus carbonate, alkali metals, alkali earth metals, ruthenium, rhodium, palladium, chromium, manganese, tantalum and combinations thereof.

5. The tool of claim 1 , wherein the first cemented metal carbide segment comprises a height of 2 to 6 mm.

6. The tool of claim 1 , wherein the first cemented metal carbide segment comprises a region proximate the non-planar interface comprising a higher concentration of a binder than a distal region of the first cemented metal carbide segment.

7. The tool of claim 1 , wherein a volume of the tip is 0.2 to 2.0 ml.

8. The tool of claim 1 , wherein the curved working surface is conical, semispherical, domed or combinations thereof.

9. The tool of claim 1 , wherein the superhard material comprises a thickest portion approximately equal to a thickest portion of the first cemented metal carbide segment.

10. The tool of claim 1 , wherein the driving mechanism is attached to a milling drum, a trenching machine, a mining machine or combinations thereof.

11. The tool of claim 1 , wherein the driving mechanism is attached to a drill pipe.

12. The tool of claim 1 , wherein the second carbide segment and the tip are brazed together with a first braze comprising a melting temperature from 700 to 1200 degrees Celsius.

13. The tool of claim 12 , wherein the melting temperature is from 800 to 970 degrees Celsius.

14. The tool of claim 13 , wherein the first braze comprises a material selected from the group consisting of silver, gold, copper, nickel, palladium, boron, chromium, silicon, germanium, aluminum, iron, cobalt, manganese, titanium, tin, gallium, vanadium, indium, phosphorus, molybdenum, platinum, zinc, and combinations thereof.

15. The tool of claim 1 , wherein the first and second metal carbide segments comprise a metal selected from the group consisting of tungsten, titanium, molybdenum, niobium, cobalt, and/or combinations thereof.

16. The tool of claim 1 , wherein a portion of the superhard material is 0.50 to 3 mm away from an interface between the first and second carbide segments.

17. The tool of claim 1 , wherein the second cemented metal carbide comprises a volume of 0.1 to 10 ml.

18. The tool of claim 1 , wherein the second cemented metal carbide comprises a generally frustoconical geometry.

19. The tool of claim 1 , wherein the first and second metal carbide segments are generally coaxial.