Cutting elements, methods for manufacturing such cutting elements, and tools incorporating such cutting elements

Abstract

The present disclosure relates to cutting elements incorporating polycrystalline diamond bodies used for subterranean drilling applications, and more particularly, to polycrystalline diamond bodies having a high diamond content which are configured to provide improved properties of thermal stability and wear resistance, while maintaining a desired degree of impact resistance, when compared to prior polycrystalline diamond bodies. In various embodiments disclosed herein, a cutting element with high diamond content includes a modified PCD structure and/or a modified interface (between the PCD body and a substrate), to provide superior performance.

What is claimed is: 
     
         1 . A method of forming a polycrystalline diamond cutting element with high diamond content, comprising:
 providing a catalyst material and a plurality of diamond particles;   subjecting the catalyst material and the diamond particles to a high temperature and high pressure process, comprising applying a cold cell pressure within the range of approximately 5.4 GPa to 6.3 GPa and a temperature within the range of approximately 1400 to 1500° C., thereby forming a polycrystalline diamond body comprising a plurality of bonded-together diamond crystals and interstitial regions between the diamond crystals, and comprising a cutting edge; and   removing the catalyst material from a first region of the diamond body proximate the cutting edge to render a plurality of the interstitial regions in the first region substantially empty, the first region extending to a depth of at least 300 microns from the cutting edge.   
     
     
         2 . A method of forming a polycrystalline diamond cutting element with high diamond content, comprising:
 providing a first diamond mixture;   providing a second diamond mixture; and   subjecting the first and second diamond mixtures to a high temperature and high pressure process in the presence of a catalyst material, such high temperature and high pressure process comprising applying a cold cell pressure within the range of approximately 5.4 to 6.3 GPa and a temperature within the range of approximately 1400 to 1500° C., thereby forming a polycrystalline diamond body comprising a first layer formed from the first diamond mixture and a second layer formed from the second diamond mixture, each layer comprising a plurality of bonded-together diamond crystals and interstitial regions between the diamond crystals,   wherein the first layer forms at least a portion of the cutting edge of the diamond body and has a first diamond volume fraction,   wherein the second layer forms at least a portion of an interface surface of the diamond body and has a second diamond volume fraction that is at least approximately 2% less than the first diamond volume fraction,   wherein the first layer comprises a sintered average grain size less than 25 microns, and   wherein the first layer has at least one of the following properties:
 an apparent porosity less than (0.1051)·(the average grain size ̂-0.3737), or 
 a leached weight loss less than (0.251)·(the average grain size ̂-0.2691), or 
 the first diamond volume fraction is greater than (0.9077)·(the average grain size ̂ 0.0221), 
   with the average grain size provided in microns.   
     
     
         3 . A method of forming a polycrystalline diamond cutting element with high diamond content, comprising:
 providing a plurality of diamond particles and a substrate material having a cobalt content of less than approximately 11% by weight; and   subjecting the diamond particles and the substrate material to a high temperature and high pressure process, comprising applying a cold cell pressure within the range of approximately 5.4 to 6.3 GPa and a temperature within the range of approximately 1400 to 1500° C., thereby forming a polycrystalline diamond body comprising a plurality of bonded-together diamond crystals and interstitial regions between the diamond crystals,   wherein at least a portion of the polycrystalline diamond body comprises a sintered average grain size less than 25 microns, and   wherein the portion of polycrystalline diamond body has at least one of the following properties:
 an apparent porosity less than (0.1051)·(the average grain size ̂-0.3737), or 
 a leached weight loss less than (0.251)·(the average grain size ̂-0.2691), or 
 the first diamond volume fraction is greater than (0.9077)·(the average grain size ̂ 0.0221), 
   with the average grain size provided in microns.