Drill bits can be made of various types of material, such as low-carbon steel, high-carbon steel, high-speed steel, titanium-coated, cobalt, carbide-tipped and diamond. Depending on the drill bit used, these power tools can bore into wood, plastics, fiberglass, metallic objects and stone.
Low-carbon drill bits are the least costly although these tools quickly become blunt with repeated use. Drill bits made of a higher percentage of carbon are slightly better in quality and they can be drilled into hardwood and soft metallic surfaces. High-speed steel drill bits are made of alloyed metals and characterized by their thermal resistance and low susceptibility to wear.
Titanium-coated bits are layered with a compact ceramic material, which enhances their durability. Cobalt drill bits can withstand high temperatures, although they are quite brittle. Carbide-tipped bits are typically used to bore into fiberglass reinforced plastics. Polycrystalline diamond bits are the sturdiest drill bit material.