Patent ID: 7913779

Claim:
A rotary drill bit for drilling subterranean formations, the rotary drill bit comprising: a bit body including a crown region predominantly comprised of a particle-matrix composite material, the particle-matrix composite material comprising a plurality of boron carbide particles dispersed throughout an aluminum-based alloy matrix material comprising: at least 75% by weight aluminum; at least 3.5% by weight copper; and at least trace amounts of at least one of iron, lithium, magnesium, manganese, nickel, scandium, silicon, tin, zirconium, and zinc; and at least one cutting structure disposed on a face of the bit body; wherein the plurality of boron carbide particles comprises between about 40% and about 60% by weight of the particle-matrix composite material, and wherein the aluminum-based alloy matrix material comprises between about 60% and about 40% by weight of the particle-matrix composite material; and wherein the plurality of boron carbide particles includes a multi-modal particle size distribution.