What are cobalt drill bits used for? Cobalt bits are made of steel, combined with a small percentage of cobalt, usually 5 to 8%. The combination of cobalt with another alloy makes the drill bits incredibly strong. 

Cobalt has an extremely high melting and boiling point, so it’s ideal for use at high temperatures – this means the drill bits can perform for a long period of time without cutting fluid or cooling, and are often used to drill through tough or coarse materials.