Drill bit reinforcing members or blanks of this invention are formed from high-strength steels having a carbon content less than about 0.3 percent by weight, a yield strength of at least 55,000 psi, a tensile strength of at least 80,000 psi, a toughness of at least 40 CVN-L, Ft-lb, and a rate of expansion percentage change less than about 0.0025%/.degree. F. during austenitic to ferritic phase transformation. In one embodiment, such steel comprises in the range of from about 0.1 to 0.3 percent by weight carbon, 0.5 to 1.5 percent by weight manganese, up to about 0.8 percent by weight chromium, 0.05 to 4 percent by weight nickel, and 0.02 to 0.8 percent by weight molybdenum. In another example, such steel comprises in the range of from about 0.1 to 0.3 percent by weight carbon, 0.9 to 1.5 percent by weight manganese, 0.1 to 0.5 percent by weight silicon, and one or more microalloying element selected from the group consisting of vanadium, niobium, titanium, zirconium, aluminum and mixtures thereof.
Drill bit reinforcing members or blanks of this invention are formed from high-strength steels having a carbon content less than about 0.3 percent by weight, a yield strength of at least 55,000 psi, a tensile strength of at least 80,000 psi, a toughness of at least 40 CVN-L, Ft-lb, and a rate of expansion percentage change less than about 0.0025%/.degree. F. during austenitic to ferritic phase transformation. In one embodiment, such steel comprises in the range of from about 0.1 to 0.3 percent by weight carbon, 0.5 to 1.5 percent by weight manganese, up to about 0.8 percent by weight chromium, 0.05 to 4 percent by weight nickel, and 0.02 to 0.8 percent by weight molybdenum. In another example, such steel comprises in the range of from about 0.1 to 0.3 percent by weight carbon, 0.9 to 1.5 percent by weight manganese, 0.1 to 0.5 percent by weight silicon, and one or more microalloying element selected from the group consisting of vanadium, niobium, titanium, zirconium, aluminum and mixtures thereof.
This invention relates to cutting inserts for earth boring bits comprising a cutting zone, wherein the cutting zone comprises first cemented hard particles and a body zone, wherein the body zone comprises second cemented hard particles. The first cemented hard particles may differ in at least one property from the second cemented hard particles. As used herein, the cemented hard particles means a material comprising hard particles in a binder. The hard particles may be at least one of a carbide, a nitride, a boride, a silicide, an oxide, and solid solutions thereof and the binder may be at least one metal selected from cobalt, nickel, iron and alloys of cobalt, nickel or iron.
An abrasive wear-resistant material includes a matrix and sintered and cast tungsten carbide pellets. A device for use in drilling subterranean formations includes a first structure secured to a second structure with a bonding material. An abrasive wear-resistant material covers the bonding material. The first structure may include a drill bit body and the second structure may include a cutting element. A method for applying an abrasive wear-resistant material to a drill bit includes providing a bit, mixing sintered and cast tungsten carbide pellets in a matrix material to provide a pre-application material, heating the pre-application material to melt the matrix material, applying the pre-application material to the bit, and solidifying the material. A method for securing a cutting element to a bit body includes providing an abrasive wear-resistant material to a surface of a drill bit that covers a brazing alloy disposed between the cutting element and the bit body.
