Shopping for the correct drill bit can get confusing fast. There are so many different options out there, which one is right for your job? We are here to help, answering all sorts of questions around drill bits, including what is a HSS drill bit? Let’s have a look and figure it out.
In short, an HSS drill bit is a drill bit made from specialist high-speed steel, they are commonly used for drilling metals but can be used in a range of materials.
HSS Drill Bit (High Speed Steel)
HSS stands for high-speed steel. It is a subcategory of tool steels. High-Speed Steel is used to make drill bits as it is a tough steel that keeps that toughness for a wide heat range.
This is important for drill bits as when in use a drill bit can heat up very quickly. With poorer steels, this can result in the drill bit losing its toughness and blunting quicker.
HSS is heat-treated when it is manufactured, this is what gives it a lot of its high heat protection. The heat treatment usually reaches over 1,200°C before being cooled!
Another factor that goes into HSS is that along with iron and carbon there are usually a few other elements added. Tungsten, cobalt, vanadium and the exotic-sounding molybdenum are commonly used.
Another additional factor in the strength of HSS drill bits is the coating. You will often see the higher end HSS drill bits advertised as having a titanium coating. This can help to improve the durability of the bit making it last longer.
There are different coatings that can be used and each has its own properties. I’m afraid this is where the material science gets a bit much for me, so I can t really say which will be best.
But let’s be honest, the difference between the coatings is only going to be small. what really matters is that HSS drill bits with a titanium coating are likely to last longer and stay sharper longer than non coated ones.
What Are They Used For?
HSS Drill Bits are commonly sold as metal, or multi-material, drill bits. They can drill steel, cast steel, alloyed and non-alloyed material, grey cast-iron, spherical-graphite cast iron, sintered iron, nickel and brass.
They can also be used in metals and plastics, although they are not needed. Cheaper drill bits can do the job through these materials just as well.
Planning on doing some heavy-duty drilling? You will want the right drill bit for the job, make sure to read these posts.