Earth-boring rotary drill bits including bit bodies having boron carbide particles in aluminum or aluminum-based alloy matrix materials, and methods for forming such bits

Abstract

Rotary drill bits for drilling subterranean formations include a bit body and at least one cutting structure disposed on a face thereof. The bit body includes a crown region comprising a particle-matrix composite material that includes a plurality of boron carbide particles dispersed throughout an aluminum or aluminum-based alloy matrix material. In some embodiments, the matrix material may include a continuous solid solution phase and a discontinuous precipitate phase. Methods of manufacturing rotary drill bits for drilling subterranean formations include infiltrating a plurality of boron carbide particles with a molten aluminum or aluminum-based material. In additional methods, a green powder component is provided that includes a plurality of particles each comprising boron carbide and a plurality of particles each comprising aluminum or an aluminum-based alloy material. The green powder component is at least partially sintered to provide a bit body, and a shank is attached to the bit body.