What is HSS Cobalt Drill Bit?
Cobalt bits are a combination of steel (or another alloy) mixed with a small percentage of cobalt, typically between 5 – 7%. Cobalt has a melting point of 1495°C and a boiling point of 2927°C, which makes it perfect for use at high temperatures. By combining a small amount of cobalt with another alloy, the results are incredible.
Both high-cobalt bits and cobalt-containing bits are high-speed steel bits. In fact, the raw material of cobalt-containing drill bits is high-speed steel, but not all high-speed steels can be called cobalt-containing drill bits. The grades of this high-speed steel material are M35 high-speed steel and M42 high-speed steel. Why is there a name for cobalt-containing drill bits?
This is because the two high-speed sheets of steel, M35 and M42, have cobalt properties in their materials. M35 has 5% cobalt and M42 has 8% cobalt. Cobalt is used in the production of heat-resistant alloys, cemented carbides, and corrosion-resistant alloys. , is an important raw material for magnetic alloys and various cobalt salts.
Why choose a cobalt drill bit?
Cobalt drill bits are incredibly strong. They can be operated at much higher speeds than a standard HSS drill bit. The ability to withstand heat means that cobalt bits perform for long periods without cooling or the need for cutting fluid.
They are most often used to cut through hardened and abrasive materials. Cobalt bits are able to cut through the most hardened metals, including bronze, cast iron, stainless steel and titanium. They are also able to cut through weld seams.
The cutting edge on a good quality cobalt bit should last for longer than a standard HSS bit. Like other HSS bits, they are corrosion-resistant, which means they should retain their condition in all storage and usage conditions they’re likely to experience. However, cobalt can be brittle. If your cobalt drill bits aren’t cared for properly or are dropped, they can break – which can prove costly.