Sensor-enabled cutting elements for an earth-boring drilling tool may comprise a substrate base, and a cutting tip at an end of the substrate base. The cutting tip may comprise a tapered surface extending from the substrate base and tapering to an apex of the cutting tip, and a sensor coupled with the cutting tip. The sensor may be configured to obtain data relating to at least one parameter related to at least one of a drilling condition, a wellbore condition, a formation condition, and a condition of the earth-boring drilling tool. The sensor-enabled cutting elements may be included on at least one of an earth-boring drill bit, a drilling tool, a bottom-hole assembly, and a drill string.

Sensor-enabled cutting elements for an earth-boring drilling tool may comprise a substrate base, and a cutting tip at an end of the substrate base. The cutting tip may comprise a tapered surface extending from the substrate base and tapering to an apex of the cutting tip, and a sensor coupled with the cutting tip. The sensor may be configured to obtain data relating to at least one parameter related to at least one of a drilling condition, a wellbore condition, a formation condition, and a condition of the earth-boring drilling tool. The sensor-enabled cutting elements may be included on at least one of an earth-boring drill bit, a drilling tool, a bottom-hole assembly, and a drill string.

A method of manufacturing a roller cone for a drill bit includes: selectively carburizing a land of the roller cone between a plurality of spots on the land for protection against erosion; after carburization, forming sockets in the roller cone at the spots; and mounting cermet inserts in the sockets.

A method of manufacturing a roller cone for a drill bit includes: selectively carburizing a land of the roller cone between a plurality of spots on the land for protection against erosion; after carburization, forming sockets in the roller cone at the spots; and mounting cermet inserts in the sockets.

A polycrystalline diamond (PCD) composite compact element comprising a PCD structure bonded to a cemented carbide substrate, in which at least a peripheral region of the substrate comprises cemented carbide material having a mean free path (MFP) characteristic of at least about 0.1 microns and at most about 0.7 microns; and an elastic limit of at least about 1.9 GPa.

A polycrystalline diamond (PCD) composite compact element comprising a PCD structure bonded to a cemented carbide substrate, in which at least a peripheral region of the substrate comprises cemented carbide material having a mean free path (MFP) characteristic of at least about 0.1 microns and at most about 0.7 microns; and an elastic limit of at least about 1.9 GPa.

A steel constituting a chisel according to the present invention includes: 0.40-0.45% by mass of carbon, 0.50-0.80% by mass of silicon, 1.00-1.30% by mass of manganese, 0.001-0.005% by mass of sulfur, 2.90-3.80% by mass of chromium, and 0.20-0.40% by mass of molybdenum, with a balance consisting of iron and an unavoidable impurity, the steel has an ideal critical diameter DI defined by Equation (1) of 600 or more:

DI=7.Math.(% C).sup.1/2.Math.(1+0.64.Math.% Si).Math.(1+4.1.Math.% Mn).Math.(1+2.83.Math.% P).Math.(10.62.Math.% S).Math.(1+2.33.Math.% Cr).Math.(1+3.14.Math.% Mo)(1).

A steel constituting a chisel according to the present invention includes: 0.40-0.45% by mass of carbon, 0.50-0.80% by mass of silicon, 1.00-1.30% by mass of manganese, 0.001-0.005% by mass of sulfur, 2.90-3.80% by mass of chromium, and 0.20-0.40% by mass of molybdenum, with a balance consisting of iron and an unavoidable impurity, the steel has an ideal critical diameter DI defined by Equation (1) of 600 or more:

DI=7.Math.(% C).sup.1/2.Math.(1+0.64.Math.% Si).Math.(1+4.1.Math.% Mn).Math.(1+2.83.Math.% P).Math.(10.62.Math.% S).Math.(1+2.33.Math.% Cr).Math.(1+3.14.Math.% Mo)(1).

A sensor element for a cutting tool (100) has a hard portion (110) having a sensing surface (112), first and second electrodes (120, 130), first and second sets of thermocouple wires (122, 132) and an electrically insulating portion. The first and second electrodes (120, 130) are arranged to allow electric current to flow when the sensing surface (112) contacts external material in response to the cutting tool engaging the external material. A first thermocouple junction (124) is operable to indicate a temperature of the first electrode and a second thermocouple junction (134) is operable to measure temperature of the second electrode.

A sensor element for a cutting tool (100) has a hard portion (110) having a sensing surface (112), first and second electrodes (120, 130), first and second sets of thermocouple wires (122, 132) and an electrically insulating portion. The first and second electrodes (120, 130) are arranged to allow electric current to flow when the sensing surface (112) contacts external material in response to the cutting tool engaging the external material. A first thermocouple junction (124) is operable to indicate a temperature of the first electrode and a second thermocouple junction (134) is operable to measure temperature of the second electrode.