摘要 |
An insert for a rock bit that includes tungsten carbide particles, and a cobalt binder disposed around the particles, wherein a grain size of the tungsten carbide particles and a content of the cobalt binder are selected to provide a fracture toughness of at least about 18 ksi (in)<SUP>0.5</SUP>, a wear number of at least about 2, and a hardness of 85 to 87 Ra is disclosed. |