Polycrystalline diamond bodies incorporating fractionated distribution of diamond particles of different morphologies
Diamond bodies and methods of manufacture are disclosed. Diamond bodies are formed from at least a bimodal, alternatively a tri-modal or higher modal, feedstock having at least one fraction of modified diamond particles with a fine particle size (0.5-3.0 μm) and at least one fraction of diamond particles with coarse particle size (15.0 to 30 μm). During high pressure-high temperature processing, fine particle sized, modified diamond particles in the first fraction preferentially fracture to smaller sizes while preserving the morphology of coarse particle sized diamond particles in the second fraction. Diamond bodies incorporating the two fractions have a microstructure including second fraction diamond particles dispersed in a continuous matrix of first fraction modified diamond particles and exhibit improved wear characteristics, particularly for wear associated with drilling of geological formations.
1. A feedstock for manufacturing a polycrystalline diamond body, the feedstock comprising:
a plurality of diamond particles including at least one fraction of modified diamond particles having a first median particle distribution D50 and at least one fraction of monocrystalline diamond particles having a second median particle distribution D50;
wherein the first median particle distribution D50 is less than the second median particle distribution D50, and
wherein at least about 40% of the first fraction of modified diamond grains have a sphericity of less than about 0.7 and at least about 75% of the second fraction of monocrystalline diamond grains have a sphericity of greater than about 0.8.
2. The feedstock of claim 1 , wherein the second median particle distribution D50 is at least about 7 times the first median particle distribution D50.
3. The feedstock of claim 1 , wherein the first fraction of modified diamond grains comprises from about 20 vol. % to 40 vol % of the diamond particles in the feedstock, and wherein the second fraction of monocrystalline diamond grains comprises from about 80 vol. % to 60 vol % of the diamond particles in the feedstock.
4. The feedstock of claim 1 , wherein the first median particle distribution D50 is from about 0.1 μm to about 3 μm.
5. The feedstock of claim 4 , wherein the first median particle distribution D50 is from about 0.5 μm to about 3 μm.
6. The feedstock of claim 1 , wherein the second median particle distribution D50 is from about 10.0 μm to about 40.0 μm.
7. The feedstock of claim 6 wherein the second median particle distribution D50 is from about 15.0 μm to about 30.0 μm.
8. The feedstock of claim 6 wherein the second median particle distribution D50 is from about 15.0 μm to about 20.0 μm.
9. The feedstock of claim 1 , wherein the at least one fraction of modified diamond particles is distributed within a volume of the at least one fraction of monocrystalline diamond particles to form a homogenous mixture.
10. A feedstock for manufacturing a polycrystalline diamond body, the feedstock comprising:
a plurality of diamond particles including a first fraction of modified diamond particles having a first median particle distribution D50, a second fraction of monocrystalline diamond particles having a second median particle distribution D50, and a third fraction of diamond particles having a third median particle distribution D50,
wherein the first median particle distribution D50 (i) is less than the second median particle distribution D50 and (ii) is less than the third median particle distribution D50,
wherein the second median particle distribution D50 (i) is greater than the first median particle distribution D50 and (ii) is greater than the third median particle distribution D50, and
wherein at least about 40% of the first fraction of modified diamond grains have a sphericity of less than about 0.7 and at least about 75% of the second fraction of monocrystalline diamond grains have a sphericity of greater than about 0.8.
11. The feedstock of claim 10 , wherein the diamond particles in the third fraction of diamond particles are modified diamond particles.
12. The feedstock of claim 10 , wherein the diamond particles in the third fraction of diamond particles are monocrystalline diamond particles.
13. The feedstock of claim 10 , wherein the first fraction of modified diamond particles comprises >0 vol. % to less than about 10 vol. % of the feedstock,
wherein the third fraction of diamond particles comprises about 20 vol. % to less than about 40 vol. % of the feedstock, and
wherein the second fraction of monocrystalline diamond particles comprises a balance (in vol. %) of the feedstock.
14. The feedstock of claim 13 , wherein the first median particle distribution D50 is from about 0.1 μm to about 3 μm.
15. The feedstock of claim 13 , wherein the second median particle distribution D50 is from about 10.0 μm to about 40.0 μm.
16. The feedstock of claim 13 , wherein the third median particle distribution D50 is from about 3.0 μm to about 10.0 μm.
17. The feedstock of claim 10 , wherein the first fraction of modified diamond particles comprises 2 vol. % to less than about 8 vol. % of the feedstock,
wherein the third fraction of diamond particles comprises about 20 vol. % to less than about 40 vol. % of the feedstock, and
wherein the second fraction of monocrystalline diamond particles comprises greater than 60 vol. % of the feedstock.
18. The feedstock of claim 17 , wherein the first median particle distribution D50 is from about 0.1 μm to about 3 μm, wherein the second median particle distribution D50 is from about 10.0 μm to about 40.0 μm, and wherein the third median particle distribution D50 is from about 3.0 μm to about 10.0 μm.
19. The feedstock of claim 10 , wherein the first fraction of modified diamond particles and the third fraction of diamond particles are distributed within a volume of the second fraction of monocrystalline diamond particles to form a homogenous mixture.