Cutting elements formed from ultra hard materials having an enhanced construction

A cutting element comprising:

• an ultra hard body comprising:
• an uppermost layer comprising a plurality of diamond bonded crystals and a plurality of interstitial regions disposed among the crystals, the uppermost layer including an outer surface that is a working surface of the body, the uppermost layer comprising:
• an outer region extending from at least a portion of the outer surface to a depth within the uppermost layer, wherein the outer region is substantially free of a catalyst material;
• and
• a remaining region that includes the catalyst material;
• an intermediate layer comprising a plurality of diamond bonded crystals and attached at one of its surfaces to the uppermost layer remaining region, the intermediate layer having a wear resistance that is less than that of the uppermost layer remaining region;
• and
• a metallic substrate attached to the ultra hard body;
• wherein the ultra hard body further comprises a lowermost layer that is interposed between and attached to the intermediate layer and the substrate, wherein the lowermost layer is formed from diamond grains having an average particle size greater than the average particle size of the diamond grains used to form the intermediate layer.

A polycrystalline diamond element comprising:

• a diamond body comprising:
• an uppermost layer comprising a plurality of bonded diamond crystals and a plurality of interstitial regions disposed among the crystals, the uppermost layer including an outer surface That is a working surface of the body, the uppermost layer comprising an outer region extending from at least a portion of the outer surface to a partial depth within the uppermost layer, and a remaining region extending from the depth, wherein the outer region is more thermally stable than the remaining region, and wherein the uppermost layer is formed from diamond gains sized greater than about 20 micrometers;
• an intermediate layer joined to the uppermost layer and comprising a plurality of bonded diamond crystals, the intermediate layer having a wear resistance that is less than that of the uppermost layer remaining region;
• and
• a metallic substrate integrally formed with the diamond body;
• wherein the intermediate layer is formed from diamond grains having an average particle size that is less than that of the diamond grains used to form in the uppermost layer.

A cutting element comprising:

• a diamond body comprising:
• an uppermost layer comprising a plurality of bonded diamond crystals and a plurality of interstitial regions disposed among the crystals, the uppermost layer including an outer surface that is a working surface of the body, the uppermost layer being formed from diamond grains having an average particle size of greater than 20 micrometers;
• and
• an intermediate layer comprising a plurality of bonded diamond crystals and attached at one of its surfaces to the uppermost layer, the intermediate layer having a wear resistance that is less than that of the uppermost layer;
• and a metallic substrate attached to the diamond body;
• wherein the uppermost layer is formed from diamond grains having an average particle size different from the diamond grains used to form the intermediate layer.

A cutting element comprising:

• a diamond body comprising:
• an uppermost layer comprising a plurality of bonded diamond crystals and a plurality of interstitial regions disposed among the crystals, the uppermost layer including an outer surface that is a working surface of the body, the uppermost layer being formed from diamond grains having an average particle size of greater than 20 micrometers;
• and
• an intermediate layer comprising a plurality of bonded diamond crystals and all ached at one of its surfaces to the uppermost layer, the intermediate layer having a wear resistance that is less than that of the uppermost layer;
• and a metallic substrate attached to the diamond body;
• wherein the diamond body further comprises a lowermost layer that is interposed between and attached to the intermediate layer and the substrate, wherein the lowermost layer is formed from diamond grains having an average particle size greater than the average particle size of the diamond grains used to form the intermediate layer.

An earth drilling drill bit comprising:

• a body having a head and having a number of blades extending away from a surface of the head, the blades adapted to engage a subterranean formation during drilling;
• a plurality of cutters disposed in the blades to contact the subterranean formation during drilling, wherein at least one of the cutters comprise:
• a diamond body comprising:
• an uppermost layer comprising a plurality of bonded diamond crystals and a plurality of interstitial regions disposed among the crystals, the uppermost layer including an outer surface that is a working surface of the body, the uppermost layer comprising:
• an outer region extending from at least a portion of the outer surface to a depth within the uppermost layer, wherein the outer region is substantially free of a catalyst material;
• and
• a remaining region that includes the catalyst material;
• an intermediate layer joined to the uppermost layer and comprising a plurality of bonded diamond crystals, the intermediate layer having a wear resistance that is less than that of the uppermost layer remaining region;
• and
• a metallic substrate attached to the body, wherein the cutter substrate is attached to the blade;
• wherein the uppermost layer is formed from diamond grains having an average particle size different from the diamond grains used to form the intermediate layer.

An earth drilling drill bit comprising:

• a body having a head and having a number of blades extending away from a surface of the head, the blades adapted to engage a subterranean formation during drilling;
• a plurality of cutters disposed in the blades to contact the subterranean formation during drilling, wherein at least one of the cutters comprise:
• a diamond body comprising:
• an uppermost layer comprising a plurality of bonded diamond crystals and a plurality of interstitial regions disposed among the crystals, the uppermost layer including an outer surface that is a working surface of the body, the uppermost layer comprising:
• an outer region extending from at least a portion of the outer surface to a depth within the uppermost layer, wherein the outer region is substantially free of a catalyst material;
• and
• a remaining region that includes the catalyst material;
• an intermediate layer joined to the uppermost layer and comprising a plurality of bonded diamond crystals, the intermediate layer having a wear resistance that is less than that of the uppermost layer remaining region;
• and
• a metallic substrate attached to the body, wherein the cutter substrate is attached to the blade;
• wherein the diamond body further comprises a lowermost layer that is interposed between and attached to the intermediate layer and the substrate, wherein the lowermost layer is formed from diamond gains having an average particle size greater than the average particle size of the diamond grains used to form the intermediate layer.