US 2023/0364675 A1 · METHODS OF FORMING POLYCRYSTALLINE COMPACTS

Abstract

Polycrystalline compacts include a polycrystalline superabrasive material comprising a first plurality of grains of superabrasive material having a first average grain size and a second plurality of grains of superabrasive material having a second average grain size smaller than the first average grain size. The first plurality of grains is dispersed within a substantially continuous matrix of the second plurality of grains. Earth-boring tools may include a body and at least one polycrystalline compact attached thereto. Methods of forming polycrystalline compacts may include coating relatively larger grains of superabrasive material with relatively smaller grains of superabrasive material, forming a green structure comprising the coated grains, and sintering the green structure. Other methods include mixing diamond grains with a catalyst and subjecting the mixture to a pressure greater than about five gigapascals (5.0 GPa) and a temperature greater than about 1,300° C. to form a polycrystalline diamond compact.

Claims17

Dependent claims

A method of forming a polycrystalline compact, comprising:

coating larger grains of superabrasive material having a first average grain size between about five microns (5 μm) and about forty microns (40 μm) with smaller grains of superabrasive material having a second average grain size between about five nanometers (5 nm) and about two microns (2 μm);
forming a green structure comprising the larger coated grains;
and
sintering the green structure by subjecting the green structure for less than about two minutes to a pressure greater than about six and a half gigapascals (6.5 GPa) and a temperature greater than about 1,500° C. to form a continuous matrix of the smaller grains including in-situ nucleated grains, to form inter-granular bonds between the larger grains and the smaller grains, to prevent growth of the larger grains, and to prevent shrinkage of the smaller grains, wherein the larger grains are dispersed within the continuous matrix, and at least some of the larger grains are non-contiguous.

1 more element

A method of forming a polycrystalline diamond compact, comprising:

mixing a first plurality of diamond grains with a second plurality of diamond grains and a catalyst for catalyzing the formation of diamond-to-diamond inter-granular bonds, the first plurality of grains having a first average grain size between about five microns (5 μm) and about forty microns (40 μm), the second plurality of grains having a second average grain size between about five nanometers (5 nm) and about two microns (2 μm);
and
controlling sintering parameters including temperature, pressure, and time including subjecting the mixture for less than about two minutes to a pressure greater than about 6.5 gigapascals (GPa) and a temperature greater than about 1,500° C. to form a polycrystalline diamond compact comprising in-situ nucleated diamond grains of hard material, the first plurality of diamond grains and the second plurality of diamond grains, to prevent growth of the first plurality of diamond grains, to prevent shrinkage of the second plurality of diamond grains, and to form a continuous matrix comprising the second plurality of diamond grains in which the first plurality of diamond grains are embedded, wherein at least some of the first plurality of grains are non-contiguous.

Dependencies are inferred from the claim text.

Methods of forming polycrystalline compacts

Life of this patent

Methods of forming polycrystalline compacts

Life of this patent

Abstract

Claims17